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{{Redirect2|Railway|Railroad}}
My name is Pansy (46 years old) and my hobbies are Origami and Baton twirling.<br><br>my homepage ... tenali.org [[http://tenali.org/groups/positive-aspects-to-get-pleasure-from-in-vietnam-and-how-to-appreciate-your-remain-cheaply/ Read Significantly more]]
[[File:BNSF GE Dash-9 C44-9W Kennewick - Wishram WA.jpg|thumb|right|upright=1.2|Four [[BNSF]] [[GE C44-9W]] diesel locomotives hauling a mixed freight train along the banks of the [[Columbia River]], between [[Kennewick, Washington|Kennewick]] and [[Wishram, Washington|Wishram]], [[Washington (state)|Washington State]], [[United States of America|USA]]]]
{{Transport}}
{{Trainstopics}}
'''Rail transport''' is a means of [[transport|conveyance of passengers and goods]], by way of wheeled vehicles running on [[Track (rail transport)|rails]]. It is also commonly referred to as train transport. In contrast to [[road transport]], where vehicles merely run on a prepared surface, rail vehicles are also directionally guided by the tracks on which they run. Track usually consists of [[steel]] rails installed on [[Railroad tie|sleepers/ties]] and [[track ballast|ballast]], on which the [[rolling stock]], usually fitted with metal [[wheel]]s, moves. However, other variations are also possible, such as slab track where the rails are fastened to a concrete foundation resting on a prepared subsurface.
 
Rolling stock in railway transport systems generally has lower frictional resistance when compared with [[highway]] vehicles and the passenger and freight cars (carriages and wagons) can be coupled into longer [[trains]]. The [[rail transport operations|operation]] is carried out by a [[railway company]], providing transport between [[train station]]s or freight customer facilities. Power is provided by [[locomotive]]s which either draw [[electrical power]] from a [[railway electrification system]] or produce their own power, usually by [[diesel engine]]s. Most tracks are accompanied by a [[railroad signaling|signalling system]]. Railways are a safe land transport system when compared to other forms of transport.<ref group=Nb>According to [http://www.railwatch.org.uk/backtrack/rw94/rw094p06.pdf this source], railways are the safest on both a per-mile and per-hour basis, whereas [[Aviation|air transport]] is safe only on a per-mile basis</ref> Railway transport is capable of high levels of passenger and cargo utilization and energy efficiency, but is often less flexible and more [[capital (economics)|capital]]-intensive than [[highway]] transport is, when lower traffic levels are considered.
 
The oldest, man-hauled railways date back to the 6th century B.C, with [[Periander]], one of the [[Seven Sages of Greece]], credited with its invention. Rail transport blossomed after the British development of the [[steam locomotive]] as a viable source of the power in the 18th and 19th centuries. With steam engines, it was possible to construct mainline railways, which were a key component of the [[industrial revolution]]. Also, railways reduced the costs of [[shipping]], and allowed for fewer lost goods, compared with shipping, which faced occasional sinking of ships. The change from canals to railways allowed for "national markets" in which prices varied very little from city to city. Studies have shown that the invention and development of the railway in Europe was one of the most important technological inventions of the late 19th century for the United States, without which, GDP would have been lower by 7.0% in 1890.
 
In the 1880s, [[electricity|electrified]] trains were introduced, and also the first tramways and rapid transit systems came into being. Starting during the 1940s, the non-electrified railways in most countries had their steam [[locomotive]]s replaced by [[diesel fuel|diesel]]-electric locomotives, with the process being almost complete by 2000. During the 1960s, electrified [[high-speed rail|high-speed railway system]]s were introduced in [[Japan]] and a few other countries. Other forms of guided ground transport outside the traditional railway definitions, such as [[monorail]] or [[Maglev (transport)|maglev]], have been tried but have seen limited use.
 
==History==
The history of the growth, decline and restoration to use of rail transport can be divided up into several discrete periods defined by the principal means of motive power used.
 
===Pre-steam===
[[File:Brno, Brno Město, historická koňská tramvaj.jpg|thumb|Horsecar in [[Brno]], Czech Republic]]
The earliest evidence of a railway was a {{convert|6|km|1|adj=on}} [[Diolkos]] [[wagonway]], which transported boats across the [[Corinth]] isthmus in Greece during the 6th century BC. Trucks pushed by slaves ran in grooves in limestone, which provided the track element. The Diolkos ran for over 600&nbsp;years.<ref>{{cite web| author=Lewis, M. J. T |title=Railways in the Greek and Roman World |url=http://www.sciencenews.gr/docs/diolkos.pdf |accessdate=11 April 2009 |format=PDF}}</ref>
 
Railways began reappearing in Europe after the [[Dark Ages (historiography)|Dark Ages]]. The earliest known record of a railway in Europe from this period is a stained-glass window in the [[Freiburg Minster|Minster of Freiburg im Breisgau]] in Germany, dating from around 1350.<ref name=GrandExperiment>{{cite book |last=Hylton |first=Stuart |title=The Grand Experiment: The Birth of the Railway Age 1820–1845 |publisher=Ian Allan Publishing |year=2007}}</ref> In 1515, [[Matthäus Lang|Cardinal Matthäus Lang]] wrote a description of the [[Reisszug]], a [[funicular|funicular railway]] at the [[Hohensalzburg Castle]] in [[Austria]]. The line originally used wooden rails and a [[hemp]] haulage rope, and was operated by human or animal power. The line still exists, albeit in updated form, and is one of the oldest railways still to operate.<ref>{{cite news | first = Reinhard | last = Kriechbaum | url = http://www.die-tagespost.de/Archiv/titel_anzeige.asp?ID=8916 | title = Die große Reise auf den Berg | work = der Tagespost | date = 15 May 2004 | accessdate = 22 April 2009 | language = German}}</ref><ref name=fm1>{{cite web | url = http://www.funimag.com/funimag10/RESZUG01.HTM | title = Der Reiszug – Part 1 – Presentation | publisher = Funimag | accessdate = 22 April 2009}}</ref>
 
By 1550, [[narrow gauge railways]] with wooden rails were common in mines in Europe.<ref>{{cite book |author=Georgius Agricola |title=[[De re metallica]] |year=1913 |isbn=0-486-60006-8}}</ref> By the 17th century, wooden wagonways were common in the United Kingdom for transporting coal from mines to canal wharfs for [[transshipment]] to boats. The world's oldest working railway, built in 1758, is the [[Middleton Railway]] in [[Leeds]]. In 1764, the first [[gravity railroad]] in the United States was built in [[Lewiston, New York]].<ref name=Porter>{{cite book | last=Porter |first=Peter |title=Landmarks of the Niagara Frontier |publisher=The Author |year=1914 | isbn=0-665-78347-7}}</ref> The first permanent tramway was the [[Leiper Railroad]] in 1810.<ref>{{cite web| url=http://www.seas.upenn.edu/~morlok/morlokpage/transp_data.html| title=First permanent railroad in the U.S. and its connection to the University of Pennsylvania| author=Morlok, Edward K.| date=11 May 2005| accessdate=19 September 2007}}</ref>
 
The first iron plate railway made with [[wrought iron]] plates on top of wooden rails, was taken into use in 1768.<ref>
at [[Coalbrookdale]] {{cite book|title=Railways (pt 1)|url=http://www.1902encyclopedia.com/R/RAI/railway-01.html|accessdate=15 February 2011|series=Encyclopædia Britannica|year=1902|isbn=1-872524-63-X}}
</ref> This allowed a variation of [[rail gauge|gauge]] to be used. At first only [[balloon loop]]s could be used for turning, but later, movable points were taken into use that allowed for switching.<ref>{{cite book |author=Vaughan, A. |year=1997 |title=Railwaymen, Politics and Money |location=London |publisher=John Murray |isbn=0-7195-5746-1}}</ref> From the 1790s, iron edge rails began to appear in the United Kingdom.<ref name="Guinness Book of Rail Facts & Feats"/> In 1803, [[William Jessop]] opened the [[Surrey Iron Railway]] in south London, arguably the world's first horse-drawn public railway.<ref>{{cite web| url=http://www.stephensonloco.fsbusiness.co.uk/surreyiron.htm| title=Surrey Iron Railway 200th – 26th July 2003| publisher=Stephenson Locomotive Society| work=Early Railways| accessdate=19 September}}</ref> The invention of the [[wrought iron]] rail by [[John Birkinshaw]] in 1820 allowed the short, brittle, and often uneven, cast iron rails to be extended to {{convert|15|ft|m}} lengths.<ref>
{{cite book|last=Skempton|first=A.W.|title=A biographical dictionary of civil engineers in Great Britain and Ireland, John Birkinshaw|pages=59–60|url=http://books.google.com/books?id=jeOMfpYMOtYC&pg=PA59|isbn=978-0-7277-2939-2|year=2002}}
</ref> These were succeeded by [[steel]] in 1857.<ref name="Guinness Book of Rail Facts & Feats">{{cite book| author=Marshall, John |title=The Guinness Book of Rail Facts & Feats |year=1979 |isbn=0-900424-56-7}}</ref>
 
===Age of steam===
[[File:5051 Earl Bathurst Cocklewood Harbour.jpg|thumb|upright=1.15|A British steam locomotive-hauled train]]
[[File:Tren a las nubes cruzando Viaducto la Polvorilla.jpg|thumb|upright=1.15|[[Tren a las Nubes]] (Train to the Clouds), located in [[Salta]], [[Argentina]] ]]
 
The development of the [[steam locomotive]] during the [[Industrial Revolution]] in the [[United Kingdom]] spurred ideas for mobile [[steam locomotive]]s that could haul trains on tracks. [[James Watt]]'s patented steam engines of 1769 (revised in 1782) were heavy low-pressure engines which were not suitable for use in locomotives.<!-- I cannot check this reference, but it is against ''patently'' incorrect information<ref>{{cite book | last =Gordon | first =W. J. | title =Our Home Railways, Volume One | publisher =Frederick Warne and Co | year =1910 | location =London | pages =7–9}}</ref>--> However, in 1804, using high-pressure steam, [[Richard Trevithick]] demonstrated the first [[locomotive]]-hauled train in [[Merthyr Tydfil]], United Kingdom.<ref>{{cite web|url=http://www.museumwales.ac.uk/en/rhagor/article/trevithic_loco/|title=Richard Trevithick's steam locomotive|date=15 December 2008|publisher=Museumwales.ac.uk|accessdate=8 May 2011}}</ref><ref>{{cite news
| title      = Steam train anniversary begins
| url        = http://news.bbc.co.uk/2/hi/uk_news/wales/3509961.stm
| publisher  = BBC
| accessdate  = 8 May 2011
| quote      = A south Wales town has begun months of celebrations to mark the 200th anniversary of the invention of the steam locomotive. Merthyr Tydfil was the location where, on 21 February 1804, Richard Trevithick took the world into the railway age when he set one of his high-pressure steam engines on a local iron master's tram rails
| date=21 February 2004}}</ref> Accompanied with [[Andrew Vivian]], it ran with mixed success,<ref name="ODNBTrevithick" >{{cite book |last=Payton |first=Philip|year=2004 |title=Oxford Dictionary of National Biography |publisher=Oxford University Press
}}</ref> breaking some of the brittle cast-iron plates.<ref name=Cannon>{{cite book| author=Chartres, J. |chapter=Richard Trevithick |editor=Cannon, John |title=Oxford Companion to British History |page=932}}</ref> Two years later, the first passenger [[horse-drawn railway]] was opened nearby between [[Swansea]] and [[Mumbles]].<ref>{{cite web| url=http://www.bbc.co.uk/wales/southwest/sites/swansea/pages/mumbles_trainanniv.shtml| title=Early Days of Mumbles Railway| date=15 February 2007| publisher=BBC| accessdate=19 September 2007}}</ref>
 
====Earliest British steam railways====
In 1811, [[John Blenkinsop]] designed the first successful and practical railway locomotive<ref>{{cite web| url=http://www.britannica.com/EBchecked/topic/69274/John-Blenkinsop| title=John Blenkinsop| work=Encyclopædia Britannica| accessdate=8 May 2011}}</ref>—a [[rack railway]] worked by a steam locomotive between Middleton Colliery and [[Leeds]] on the [[Middleton Railway]]. The locomotive, ''[[Salamanca (locomotive)|Salamanca]]'', was built the following year.<ref name="Ellis">{{cite book |title=The Pictorial Encyclopedia of Railways |last=Ellis |first=Hamilton |publisher=Hamlyn Publishing Group |year=1968}}</ref>{{rp|20}} In 1825, [[George Stephenson]] built the ''[[Locomotion No 1|Locomotion]]'' for the [[Stockton and Darlington Railway]], north east England, which was the first public steam railway in the world. In 1829, he built ''[[Stephenson's Rocket|The Rocket]]'' which was entered in and won the [[Rainhill Trials]]. This success led to Stephenson establishing his company as the pre-eminent builder of steam locomotives used on railways in the United Kingdom, the United States and much of Europe.<ref name="Ellis"/>{{rp|24–30}}
 
In 1830, the first [[inter-city rail|intercity]] railway, the [[Liverpool and Manchester Railway]], opened. The gauge was that used for the early wagonways and had been adopted for the Stockton and Darlington Railway.<ref>{{cite web| url=http://www.spartacus.schoolnet.co.uk/RAliverpool.htm| title=Liverpool and Manchester| accessdate=19 September 2007}}</ref> The {{RailGauge|sg}} width became known as the international [[standard gauge]], used by about 60% of the world's railways. This spurred the spread of rail transport outside the UK.
 
By the early 1850s Britain had over {{convert|7000|mi}} of railway, a stunning achievement given that only twenty years had elapsed since the opening of the Liverpool and Manchester Railway.<ref name=Wolmar>{{cite book| author=Wolmar, Christian |chapter=Joining up Europe|title=Blood iron and gold: how the railways transformed the World|publisher=Atlantic Books |year=2009|isbn=978-1-84887-170-0|page=94}}</ref>
 
====Early railroads in the US====
Railroads (as they are known in the US) were built on a far larger scale than those in Continental Europe, both in terms of the distances covered and also in the [[loading gauge]] adopted, which allowed for heavier locomotives and double-deck trains. The railroad era in the United States began in 1830 when Peter Cooper's locomotive, [[Tom Thumb (locomotive)|''Tom Thumb'']], first steamed along {{convert|13|mi}} of [[Baltimore and Ohio Railroad|Baltimore and Ohio]] railroad track.<ref>{{cite web|title=The History of the Tom Thumb – Peter Cooper |publisher=Inventors.about.com|url=http://inventors.about.com/library/inventors/bl_tom_thumb.htm|accessdate=8 May 2011}}</ref> In 1833, the nation's second railroad ran {{convert|136|mi}} from Charleston to Hamburg in South Carolina.<ref>{{cite web | url=http://www.railga.com/charlhmbrg.html | title=Charleston & Hamburg Railroad | publisher=Railga.com | accessdate=8 May 2011 | author=Storey, Steve}}</ref> Not until the 1850s, though, did railroads offer long distance service at reasonable rates. A journey from Philadelphia to Charleston involved eight different gauges, which meant that passengers and freight had to change trains seven times. Only at places like Bowling Green, Kentucky, the railroads were connected to one another.
 
The [[Baltimore and Ohio Railroad]] that opened in 1830 was the first to evolve from a single line to a network in the United States.<ref>{{cite book |title=The Great Road: The Building of the Baltimore and Ohio, the Nation's First Railroad, 1828–1853 |last=Dilts |first=James D. |authorlink= |year=1996 |publisher=Stanford University Press |location=Palo Alto, CA |isbn=978-0-8047-2629-0 |page=26 |url=http://books.google.com/?id=JjrCWPwvHzIC&lpg=PR18&dq=dilts%20b%26o&pg=PA26#v=onepage&q=first |accessdate=}}</ref> By 1831, a steam railway connected Albany and Schenectady, New York, a distance of {{convert|16|mi}}, which was covered in 40 minutes.<ref>"The Journal of Ebenezer Mattoon Chamberlain 1832-5", ''Indiana Magazine of History'', Vol. XV, September 1919, No. 3, p.233ff.</ref>
 
The years between 1850 and 1890 saw phenomenal growth in the US railroad system, which at its peak constituted one third of the world's total mileage.<ref>Wolmar (2009) p.xiii.</ref>{{Failed verification|date=February 2012}} Although the [[American Civil War]] placed a temporary halt to major new developments, the conflict did demonstrate the enormous strategic importance of railways at times of war. After the war, major developments include the first elevated railway built in New York in 1867 as well as the symbolically important [[First Transcontinental Railroad|first transcontinental railroad]] completed in 1869.<ref>{{cite book| title=Nothing Like It In The World; The men who built the Transcontinental Railroad 1863–1869| last= Ambrose |first=Stephen E.|year=2000|publisher=Simon & Schuster| isbn=0-684-84609-8 |url=http://books.google.com/?id=TZp_GT7PscIC&lpg=PP1&dq=ambrose%20nothing%20like%20it&pg=PP1#v=onepage&q=}}</ref>
 
===Electrification and dieselisation===
[[File:Shinkansen type 0 Hikari 19890506a.jpg|thumb|0-Series Shinkansen, introduced in 1964, triggered the intercity train travel boom.]]
[[File:CTA tracks.jpg|thumb|Elevated section of the [[Chicago 'L']]]][[File:Citadis dublin.jpg|thumb|[[Luas]] in [[Dublin]], Ireland]]
Experiments with electrical railways were started by [[Robert Davidson (inventor)|Robert Davidson]] in 1838. He completed a battery-powered carriage capable of {{convert|6.4|km/h|0|abbr=on}}. The [[Gross-Lichterfelde Tramway]] was the first to use electricity fed to the trains en route, when it opened in 1881. [[Overhead wire]]s were taken into use in the [[Mödling and Hinterbrühl Tram]] in Austria in October 1883. At first, this was taken into use on [[tram]]ways that, until then, had been horse-drawn [[tram]]cars. The first conventional completely electrified railway mainline was the 106&nbsp;km [[Valtellina]] line in Italy that was opened on 4 September 1902.
 
During the 1890s, many large cities, such as [[London Underground|London]], [[Paris Métro|Paris]] and [[New York City Subway|New York City]] used the new technology to build [[rapid transit]] for urban commuting. In smaller cities, tramways became common and were often the only mode of [[public transport]] until the introduction of buses in the 1920s. In North America, [[interurban]]s became a common mode to reach suburban areas. At first, all electric railways used [[direct current]] but, in 1904, the [[Stubaitalbahn|Stubaital Line]] in Austria opened with [[alternating current]].<ref>{{cite book |title=Communication gjennom 100 år |last=Tokle |first=Bjørn |year=2003 |page=54 |publisher=[[Chr. Salvesen & Chr. Thams's Communications Aktieselskab]] |location=Meldal |language=Norwegian}}</ref>
 
Steam locomotives require large pools of labour to clean, load, maintain and run. After [[World War II]], dramatically increased labour costs in developed countries made steam an increasingly costly form of motive power. At the same time, the war had forced improvements in internal combustion engine technology that made diesel locomotives cheaper and more powerful. This caused many [[railway companies]] to initiate programmes to convert all unelectrified sections from steam to [[diesel locomotive|diesel locomotion]].
 
Following the large-scale construction of motorways after the war, rail transport became less popular for commuting and air transport started taking large market shares from long-haul passenger trains. Most tramways were either replaced by rapid transits or buses, while high transshipment costs caused short-haul freight trains to become uncompetitive. The [[1973 oil crisis]] led to a change of mind set and most tram systems that had survived into the 1970s remain today. At the same time, [[containerization]] allowed freight trains to become more competitive and participate in [[intermodal freight transport]]. With the 1964 introduction of the [[Shinkansen]] [[high-speed rail]] in Japan, trains could again have a dominant position on intercity travel. During the 1970s, the introduction of automated rapid transit systems allowed cheaper operation. The 1990s saw an increased focus on [[accessibility]] and low-floor trains. Many tramways have been upgraded to [[light rail]] and many cities that closed their old tramways have reopened new light railway systems.
 
===Innovations===
Many benchmarks in equipment and infrastructure led to the growing use of railways. Some innovative features taking place in the 19th and 20th centuries included wood cars replaced with all-steel cars, which provided better safety and maintenance; [[iron]] rails replaced with [[steel]] rails, which provided higher speed and capacity with lower weight and cost; stove-heated cars to steam-heating cars, piped from locomotive; [[gas lighting]] to [[electric lighting]], with use of [[Battery (electricity)|battery]]/[[alternator]] unit beneath the car; development of [[air-conditioning]] with additional underbody equipment and ice compartment. Some innovative rolling stock included the lightweight, diesel-powered [[streamliner]], which was a modernistic, aerodynamically styled train with flowing contours; then came the ultra-lightweight car with [[internal combustion engine]] in each train's power car; others included the dome car, turbined-powered trains, bilevel rolling stock, and the high-tech/high-speed electric trains.<ref name="EuDaly, K, et al. 2009. Complete Book of North American Railroading">EuDaly, K, Schafer, M, Boyd, Jim, Jessup, S, McBridge, A, Glischinksi, S. (2009). The Complete Book of North American Railroading. Voyageur Press. 1–352 pgs.</ref>
 
Even more, in the first half of the 20th century, infrastructure elements adopted technological changes including the continuously welded rail that was {{convert|1/4|mi}} long; concrete tie usage; double tracking major lines; [[Intermodal freight transport|intermodal]] terminal and handling technology; advances in diesel-electric propulsion to include [[AC motor|AC]] traction systems and propulsion braking systems; and [[just-in-time (business)|just-in-time]] inventory control. Beyond technology, even management of systems saw improvements with the adoption of [[environmental impact]] concerns; heightened concern of employee and [[public safety]]; introduction of [[urban area]] rail networks and public agencies to manage them; and downsizing of industry employment with greater use of [[contractors]] and [[consultants]].<ref name="AREMA. 2003. Practical Guide to Railway Engineering">American Railway Engineering and Maintenance of Way Association Committee 24 – Education and Training. (2003). Practical Guide to Railway Engineering. AREMA, 2nd Ed.</ref>
 
==Trains==
{{Main|Train}}
A train is a connected series of rail vehicles that move along the track. Propulsion for the train is provided by a separate locomotive or from individual motors in self-propelled multiple units. Most trains carry a revenue load, although non-revenue cars exist for the railway's own use, such as for [[maintenance-of-way]] purposes. The [[railroad engineer|engine driver]] (engineer in North America) controls the locomotive or other power cars, although [[people mover]]s and some rapid transits are under automatic control.
 
===Haulage===
[[File:2TE10U Russian Locomotive.jpg|thumb|Russian 2TE10U Diesel-electric locomotive]]Traditionally, trains are pulled using a locomotive. This involves one or more powered vehicles being located at the front of the train, providing sufficient [[tractive force]] to haul the weight of the full train. This arrangement remains dominant for freight trains and is often used for passenger trains. A [[push-pull train]] has the end passenger car equipped with a driver's cab so the engine driver can remotely control the locomotive. This allows one of the locomotive-hauled train's drawbacks to be removed, since the locomotive need not be moved to the front of the train each time the train changes direction. A [[railroad car]] is a vehicle used for the haulage of either passengers or freight.
 
A multiple unit has powered wheels throughout the whole train. These are used for rapid transit and tram systems, as well as many both short- and long-haul passenger trains. A [[railcar]] is a single, self-powered car, and may be electrically-propelled or powered by a [[diesel engine]]. Multiple units have a driver's cab at each end of the unit and were developed following the ability to build [[electric motor]]s and [[engine]]s small enough to fit under the coach. There are only a few freight multiple units, most of which are high-speed post trains.
 
===Motive power===
[[File:HŽ 7123 series DMU (06).JPG|thumb|A [[RegioSwinger]] multiple unit of the [[Croatian Railways]]]]
[[Steam locomotive]]s are locomotives with a [[steam engine]] that provides adhesion. [[Coal]], [[petroleum]], or [[wood]] is burned in a [[firebox (steam engine)|firebox]], boiling water in the [[fire-tube boiler|boiler]] to create pressurized steam. The steam travels through the [[smokebox]] before leaving via the chimney or smoke stack. In the process, it powers a [[piston]] that transmits power directly through a [[connecting rod]] (US: main rod) and a [[crankpin]] (US: wristpin) on the [[driving wheel]] (US main driver) or to a [[crankshaft|crank]] on a driving axle. Steam locomotives have been phased out in most parts of the world for economical and safety reasons, although many are preserved in working order by [[heritage railway]]s.
 
[[Electric locomotive]]s draw power from a stationary source via an [[Overhead lines|overhead wire]] or [[third rail]]. Some also or instead use a [[Battery (electricity)|battery]]. In locomotives that are powered by high voltage [[alternating current]], a [[transformer]] in the locomotive converts the high voltage, low current power to low voltage, high current used in the [[electric motor|traction motor]]s that power the wheels. Modern locomotives may use [[Electric motor#Three-phase AC induction motors|three-phase AC induction motors]] or [[direct current]] motors.  Under certain conditions, electric locomotives are the most powerful traction.{{citation needed|date=October 2013}} They are also the cheapest to run and provide less noise and no local air pollution.{{citation needed|date=October 2013}} However, they require high capital investments both for the [[overhead lines]] and the supporting infrastructure, as well as the generating station that is needed to produce electricity. Accordingly, electric traction is used on urban systems, lines with high traffic and for high-speed rail.
 
[[Diesel locomotive]]s use a diesel engine as the [[prime mover (locomotive)|prime mover]]. The energy transmission may be either [[diesel-electric transmission|diesel-electric]], diesel-mechanical or diesel-hydraulic but diesel-electric is dominant. [[Electro-diesel locomotive]]s are built to run as diesel-electric on unelectrified sections and as electric locomotives on electrified sections.
 
Alternative methods of motive power include [[maglev (transport)|magnetic levitation]], [[horse-drawn railway|horse-drawn]], [[funicular|cable]], gravity, [[pneumatics]] and [[gas turbine]].
 
===Passenger trains===
[[File:InterCity2 - passenger car interior.jpg|thumb|Interior view of the top deck of a [[VR Group|VR]] InterCity2 [[Bilevel rail car|double-deck carriage]]]]A passenger train travels between stations where passengers may embark and disembark. The oversight of the train is the duty of a [[conductor (transportation)|guard/train manager]]. Passenger trains are part of public transport and often make up the stem of the service, with buses feeding to stations. Passenger trains can involve a variety of functions including long distance intercity travel, daily commuter trips, or local urban transit services. They even include a diversity of vehicles, operating speeds, right of way requirements, and service frequency. Passenger trains usually can be divided into two operations: intercity railway and intracity transit. Whereas as intercity railway involve higher speeds, longer routes, and lower frequency (usually scheduled), intracity transit involves lower speeds, shorter routes, and higher frequency (especially during peak hours).<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
[[Inter-city rail|Intercity trains]] are long-haul trains that operate with few stops between cities. Trains typically have amenities such as a [[dining car]]. Some lines also provide over-night services with [[sleeping car]]s. Some long-haul trains have been given a [[lists of named passenger trains|specific name]]. [[Regional rail|Regional trains]] are medium distance trains that connect cities with outlying, surrounding areas, or provide a regional service, making more stops and having lower speeds. [[Commuter rail|Commuter train]]s serve suburbs of urban areas, providing a daily [[commuting]] service. [[Airport rail link]]s provide quick access from city centres to [[airport]]s.
 
[[High-speed rail]] are special inter-city trains that operate at much higher speeds than conventional railways, the limit being regarded at {{convert|200|to|320|km/h}}. High-speed trains are used mostly for long-haul service and most systems are in Western Europe and East Asia. The [[land speed record for railed vehicles|speed record]] is {{convert|574.8|km/h|abbr=on}}, set by a modified French [[TGV]].<ref>{{cite news| url=http://www.cnn.com/2007/WORLD/europe/04/03/TGVspeedrecord.ap/index.html| title=French train breaks speed record| date=4 April 2007| accessdate=3 April 2007| agency=Associated Press| work=[[CNN]] |archiveurl = http://web.archive.org/web/20070407194558/http://www.cnn.com/2007/WORLD/europe/04/03/TGVspeedrecord.ap/index.html <!-- Bot retrieved archive --> |archivedate = 7 April 2007| authorlink= Associated Press}}</ref><ref>{{cite news| url=http://www.bloomberg.com/apps/news?pid=newsarchive&sid=aW23Aw20niIo&refer=europe| title=French TGV Sets Record, Reaching 357 Miles an Hour (Update2)| author=Fouquet, Helene and Viscousi, Gregory| publisher=Bloomberg L.P.| date=3 April 2007 | accessdate=8 May 2011}}</ref> [[Maglev (transport)|Magnetic levitation]] trains such as the Shanghai airport train use under-riding magnets which attract themselves upward towards the underside of a guideway and this line has achieved somewhat higher peak speeds in day-to-day operation than conventional high-speed railways, although only over short distances. Due to their heightened speeds, route alignments for high-speed rail tend to be steeper grades and broader curves compared to conventional railways.
 
Their high kinetic energy translates to higher horsepower-to-ton ratios (e.g. {{convert|20|hp/ST|disp=or}}); this allows trains to accelerate and maintain higher speeds and negotiate steep grades as momentum builds up and recovered in downgrades (reducing cut, fill, and tunneling requirements). Since lateral forces act on curves, curvatures are designed with the highest possible radius. All these features are dramatically different from freight operations, thus justifying exclusive high-speed rail lines if it is economically feasible.<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/> [[File:Passenger-rail.JPG|thumb|Rail Network in Paris, France]]
 
[[Higher-speed rail]] services are intercity rail services that have top speeds higher than conventional intercity trains but the speeds are not as high as those in the high-speed rail services. These services are provided after improvements to the conventional rail infrastructure in order to support trains that can operate safely at higher speeds.
 
[[Rapid transit]] is an intracity system built in large cities and has the highest capacity of any passenger transport system. It is grade separated and commonly built underground or elevated. At street level, smaller [[tram]]s can be used. [[Light rail]]s are upgraded trams that have step-free access, their own right-of-way and sometimes sections underground. [[Monorail]] systems operate as elevated, medium capacity systems. A [[people mover]] is a driverless, grade-separated train that serves only a few stations, as a shuttle. Due to the wide variety of rapid transit systems without much uniformity, route alignment vary widely with diverse right-of-ways (private land, side of road, street median) and [[track geometry|geometric characteristics]] (sharp or broad curves, steep or gentle grades). For instance, the [[Chicago El]] trains are designed with extremely short cars to negotiate the sharp curves in the [[The Loop (Chicago Transit Authority)|Loop]]. NJ's [[Port Authority Trans-Hudson|PATH]] have similar-sized cars to accommodate curves in the trans-Hudson tunnels. San Francisco's [[BART]] operate large cars on its well-engineered routes.<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
===Freight train===
{{main|Rail freight transport}}
[[File:Wagons 550.jpg|thumb|Bulk cargo of minerals]]
 
A freight train hauls [[cargo]] using [[goods wagon|freight car]]s specialized for the type of goods. Freight trains are very efficient, with economy of scale and high energy efficiency. However, their use can be reduced by lack of flexibility, if there is need of transshipment at both ends of the trip due to lack of tracks to the points of pick-up and delivery. Authorities often encourage the use of cargo rail transport due to its environmental profile.<ref>{{cite news| url=http://www.theenvironmentalblog.org/environmental-issues/| title=Environmental Issues| publisher=The Environmental Blog| date=3 April 2007 | accessdate=10 Oct 2010}}</ref>
 
[[Containerization|Container trains]] have become the dominant type in the US for non-bulk haulage. Containers can easily be transshipped to other modes, such as ships and trucks, using cranes. This has succeeded the [[boxcar]] (wagon-load), where the cargo had to be loaded and unloaded into the train manually. The intermodal [[containerization]] of cargo has revolutionized the [[supply chain]] [[logistics]] industry, reducing ship costs significantly. In Europe, the [[Goods van#Sliding wall wagons|sliding wall wagon]] has largely superseded the [[Goods van|ordinary covered wagons]]. Other types of cars include [[refrigerator car]]s, [[stock car (rail)|stock cars]] for livestock and [[autorack]]s for road vehicles. When rail is combined with road transport, a [[roadrailer]] will allow [[semi-trailer|trailer]]s to be driven onto the train, allowing for easy transition between road and rail.
 
[[Bulk material handling|Bulk handling]] represents a key advantage for rail transport. Low or even zero transshipment costs combined with energy efficiency and low inventory costs allow trains to handle [[bulk cargo|bulk]] much cheaper than by road. Typical bulk cargo includes coal, ore, grains and liquids. Bulk is transported in [[gondola (rail)|open-topped car]]s, [[hopper car]]s and [[tank car]]s.
 
==Infrastructure==
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===Right of way===
Railway tracks are laid upon land owned or leased by the railway company. Owing to the desirability of maintaining modest grades, rails will often be laid in circuitous routes in hilly or mountainous terrain. Route length and grade requirements can be reduced by the use of alternating [[cutting (transportation)|cuttings]], bridges and tunnels—all of which can greatly increase the capital expenditures required to develop a right of way, while significantly reducing operating costs and allowing higher speeds on longer radius curves. In densely urbanized areas, railways are sometimes laid in tunnels to minimize the effects on existing properties.
 
===Trackage===
{{main|Trackage}}
[[File:European railway map.jpg|thumb|Map of railways in Europe with main operational lines shown in black, [[heritage railway]] lines in green and former routes in light blue]]
[[File:Eastbound over SCB.jpg|thumb||Long freight train crossing the Stoney Creek viaduct on the [[Canadian Pacific Railway]] in southern [[British Columbia]]]]
Track consists of two parallel steel rails, anchored [[perpendicular]] to members called [[railroad tie|ties]] (sleepers) of timber, concrete, steel, or plastic to maintain a consistent distance apart, or [[rail gauge]]. Rail gauges are usually categorised as [[Standard gauge]] ({{RailGauge|1435mm|disp=or}}) used on approximately 60% of the world's existing railway lines, [[Broad gauge]] and [[Narrow gauge]]. In addition to the rail gauge, the tracks will be laid to conform with a [[Loading gauge]] which defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures.
 
The track guides the conical, flanged wheels, keeping the cars on the track without active steering and therefore allowing trains to be much longer than road vehicles. The rails and ties are usually placed on a foundation made of compressed earth on top of which is placed a bed of [[track ballast|ballast]] to distribute the load from the ties and to prevent the track from [[buckling]] as the ground settles over time under the weight of the vehicles passing above.
 
The ballast also serves as a means of drainage. Some more modern track in special areas is attached by [[direct fixation]] without ballast. Track may be prefabricated or assembled in place. By [[Thermite welding|welding]] rails together to form lengths of [[continuous welded rail]], additional wear and tear on rolling stock caused by the small surface gap at the joints between rails can be counteracted; this also makes for a quieter ride (passenger trains).
 
On curves the outer rail may be at a higher level than the inner rail. This is called superelevation or [[cant (road/rail)|cant]]. This reduces the forces tending to displace the track and makes for a more comfortable ride for standing livestock and standing or seated passengers. A given amount of superelevation will be the most effective over a limited range of speeds.
 
[[Railroad switch|Turnouts]], also known as points and switches, are the means of directing a train onto a diverging section of track. Laid similar to normal track, a point typically consists of a [[Switch frog|frog]] (common crossing), check rails and two switch rails. The switch rails may be moved left or right, under the control of the signalling system, to determine which path the train will follow.
 
Spikes in wooden ties can loosen over time, but split and rotten ties may be individually replaced with new wooden ties or concrete substitutes. Concrete ties can also develop cracks or splits, and can also be replaced individually. Should the rails settle due to soil subsidence, they can be lifted by specialized machinery and additional ballast tamped under the ties to level the rails.
 
Periodically, ballast must be removed and replaced with clean ballast to ensure adequate drainage. Culverts and other passages for water must be kept clear lest water is impounded by the trackbed, causing landslips. Where trackbeds are placed along rivers, additional protection is usually placed to prevent streambank erosion during times of high water. Bridges require inspection and maintenance, since they are subject to large surges of stress in a short period of time when a heavy train crosses.
 
===Train inspection systems===
[[File:HBD DD1.jpg|thumb|A [[Defect detector#Sensors|Hot bearing detector]] w/ dragging equipment unit]]The inspection of railway equipment is essential for the safe movement of trains. Many types of [[defect detector]]s are in use on the world's railroads. These devices utilize technologies that vary from a simplistic paddle and switch to [[infrared]] and laser scanning, and even [[Ultrasonic testing|ultrasonic audio analysis]]. Their use has avoided many rail accidents over the 70 years they have been used.
 
===Signalling===
[[File:LeicesterAndSwannington02A.jpg|200px|right|thumb|[[Bardon Hill]] box in [[England]] is a [[Midland Railway]] box dating from 1899, although the original mechanical lever frame has been replaced by electrical switches. Seen here in 2009.]]
Railway signalling is a system used to control railway traffic safely to prevent trains from colliding. Being guided by fixed [[Track (rail transport)|rails]] with low friction, trains are uniquely susceptible to collision since they frequently operate at speeds that do not enable them to stop quickly or within the driver's sighting distance. Most forms of train control involve movement authority being passed from those responsible for each section of a rail network to the train crew. Not all methods require the use of signals, and some systems are specific to [[single track (rail)|single track]] railways.
 
The signalling process is traditionally carried out in a [[signal box]], a small building that houses the [[lever frame]] required for the signalman to operate switches and signal equipment. These are placed at various intervals along the route of a railway, controlling specified sections of track. More recent technological developments have made such operational doctrine superfluous, with the centralization of signalling operations to regional control rooms. This has been facilitated by the increased use of computers, allowing vast sections of track to be monitored from a single location. The common method of [[Railway signalling#Blocks|block signalling]] divides the track into zones guarded by combinations of block signals, operating rules, and automatic-control devices so that only one train may be in a block at any time.
 
===Electrification===
The electrification system provides electrical energy to the trains, so they can operate without a prime mover on board. This allows lower operating costs, but requires large capital investments along the lines. Mainline and tram systems normally have overhead wires, which hang from poles along the line. Grade-separated rapid transit sometimes use a ground [[third rail]].
 
Power may be fed as [[direct current|direct]] or [[alternating current]]. The most common DC voltages are 600 and 750&nbsp;V for tram and rapid transit systems, and 1,500&nbsp; and 3,000&nbsp;V for mainlines. The two dominant AC systems are [[15 kV AC]] and [[25 kV AC]].
 
===Stations===
[[File:Rang gueter bahnhof small.jpg|thumb|right|250px|Goods station in [[Lucerne]], Switzerland]]
A railway station serves as an area where passengers can board and alight from trains. A [[goods station]] is a yard which is exclusively used for loading and unloading cargo. Large passenger stations have at least one building providing conveniences for passengers, such as purchasing tickets and food. Smaller stations typically only consist of a [[railway platform|platform]]. Early stations were sometimes built with both passenger and goods facilities.<ref>{{cite journal| title=The Inception of the English Railway Station| journal=[[Architectural History]]| volume=4| year=1961| pages=63–76| doi=10.2307/1568245| jstor=1568245| publisher=SAHGB Publications Limited }}</ref>
 
Platforms are used to allow easy access to the trains, and are connected to each other via [[underpass]]es, [[footbridge]] and level crossings. Some large stations are built as [[cul-de-sac]], with trains only operating out from one direction. Smaller stations normally serve local residential areas, and may have connection to feeder bus services. Large stations, in particular [[central station]]s, serve as the main [[transport hub|public transport hub]] for the city, and have transfer available between rail services, and to rapid transit, tram or bus services.
 
==Operations==
 
===Ownership===
[[File:UP 6670.jpg|thumb|In the United States, railroads such as the [[Union Pacific]] traditionally own and operate both their rolling stock and infrastructure, with the company itself typically being privately owned.]]
 
Since the 1980s, there has been an increasing trend to split up railway companies, with companies owning the rolling stock separated from those owning the infrastructure. This is particularly true in Europe, where this arrangement is required by the European Union. This has allowed open access by any train operator to any portion of the European railway network.
 
In the U.S., virtually all rail networks and infrastructure outside the [[Northeast corridor|Northeast Corridor]] are privately owned by freight lines. Passenger lines, primarily [[Amtrak]], operate as tenants on the freight lines. Consequently, operations must be closely synchronized and coordinated between freight and passenger railroads, with passenger trains often being dispatched by the host freight railroad. Due to this shared system, both are regulated by the [[Federal Railroad Administration]] (FRA) and follow the [[American Railway Engineering and Maintenance-of-Way Association|AREMA]] standards for track work and [[Association of American Railroads|AAR]] standards for vehicles.<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
===Financing===
The main source of income for railway companies is from [[train ticket|ticket]] revenue (for passenger transport) and shipment fees for cargo. Discounts and monthly passes are sometimes available for frequent travellers. Freight revenue may be sold per container slot or for a whole train. Sometimes, the shipper owns the cars and only rents the haulage. For passenger transport, [[advertisement]] income can be significant.
 
Government may choose to give subsidies to rail operation, since rail transport has fewer [[externalities]] than other dominant modes of transport. If the railway company is state-owned, the state may simply provide direct subsidies in exchange for an increased production. If operations have been privatized, several options are available. Some countries have a system where the infrastructure is owned by a government agency or company—with open access to the tracks for any company that meets safety requirements. In such cases, the state may choose to provide the tracks free of charge, or for a fee that does not cover all costs. This is seen as analogous to the government providing free access to roads. For passenger operations, a direct subsidy may be paid to a public-owned operator, or [[public service obligation]] tender may be helt, and a time-limited contract awarded to the lowest bidder.
 
U.S.'s national passenger rail service, [[Amtrak]], is a private railroad company chartered by the government. Similarly, Canada's [[Via Rail]] system operates in the same fashion. As private passenger services lost significant ground in competition to the automobile and airplane and was forced out the market, they became [[shareholder]]s of Amtrak either with a cash entrance fee or relinquishing their locomotives and rolling stock. Government aid supports Amtrak by supplying start-up [[capital (economics)|capital]] and makes up for loses at end of the [[fiscal year]].<ref name="EuDaly, K, et al. 2009. Complete Book of North American Railroading"/>
 
===Safety===
[[File:Train wreck at Montparnasse 1895.jpg|thumb|upright=1.1|Train crash at [[Gare Montparnasse|Montparnasse Station]], Paris, France, in 1895]]
 
Rail transport is one of the safest forms of land travel.<ref>{{Cite report |title=National Transportation Statistics. Table 2-1: Transportation Fatalities by Mode |url=http://www.bts.gov/publications/national_transportation_statistics/html/table_02_01.html |author= U.S. Bureau of Transportation Statistics |year=2010 |publisher= |accessdate=14 February 2010 |docket= }}</ref> Trains can travel at very high speed, but they are heavy, are unable to deviate from the track and require a great distance to stop. Possible accidents include [[derailment]] (jumping the track), a collision with another train or collision with an automobile or other vehicle at [[level crossing]]s. The last accounts for the majority of rail accidents and casualties. The most important safety measures to prevent accidents are strict operating rules, e.g. [[railway signalling]] and gates or [[grade separation]] at crossings. [[Train whistle]]s, bells or horns warn of the presence of a train, while trackside signals maintain the distances between trains.
 
An important element in the safety of many high-speed inter-city networks such as Japan's [[Shinkansen]] is the fact that trains only run on dedicated railway lines, without level crossings. This effectively eliminates the potential for collision with automobiles, other vehicles and pedestrians, vastly reduces the likelihood of collision with other trains and helps ensure services remain timely.
 
In order to ensure the highest possible degree of safety, independent scrutiny and assessment of safety-critical products and processes is of vital importance.<ref>[http://www.sgs.com/en/Logistics/Transportation/Rail/Rail-Assessment-and-Auditing-Services.aspx Rail Assessment and Auditing Services], Retrieved 08/07/2013</ref>
 
===Maintenance===
As in any [[infrastructure]] asset, railways must keep up with periodic inspection and maintenance in order to minimize effect of infrastructure failures that can disrupt freight revenue operations and passenger services. Because passengers are considered the most ''crucial cargo'' and usually operate at higher speeds, steeper grades, and higher capacity/frequency, their lines are especially important. Inspection practices include [[track geometry car]]s or walking inspection. Curve maintenance especially for transit services includes gauging, fastener tightening, and rail replacement. In order to ensure the highest possible quality and gain the specialized skills<ref>[http://www.sgs.com/en/Logistics/Transportation/Rail/Rail-Industry-Supplier-Accreditation-RISAS-Services.aspx Rail Industry Supplier Accreditation Services], Retrieved 08/07/2013</ref> and expertise for a specific project, a Railway Undertaking (RU) or subcontractor look often for professional outsourcing staff.<ref>[http://www.sgs.com/en/Logistics/Transportation/Rail/Competent-Person-Provision-CPP-Services-for-Rail-CORRELXpert.aspx Competent Person Provision (CPP) Services for Rail], Retrieved 08/07/2013</ref>
 
Rail corrugation is a common issue with transit systems due to the high number of light-axle, wheel passages which result in grinding of the wheel/rail interface. Since maintenance may overlap with operations, maintenance windows (nighttime hours, [[off-peak]] hours, altering train schedules or routes) must be closely followed. In addition, passenger safety during maintenance work (inter-track fencing, proper storage of materials, track work notices, hazards of equipment near states) must be regarded at all times. At times, maintenance access problems can emerge due to tunnels, elevated structures, and congested cityscapes. Here, specialized equipment, smaller versions of conventional maintenance gear are used.<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
Unlike [[highways]] or [[road network]]s where capacity is disaggregated into unlinked trips over individual route segments, railway capacity is fundamentally considered a network system. As a result, many components are causes and effects of system disruptions. Maintenance must acknowledge the vast array of a route's performance (type of train service, origination/destination, seasonal impacts), line's capacity (length, terrain, number of tracks, types of train control), train's throughput (max speeds, acceleration/deceleration rates), and service features with shared passenger-freight tracks (sidings, terminal capacities, switching routes, and design type).<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
==Impact==
 
===Energy===
[[File:BNSF 5350 20040808 Prairie du Chien WI.jpg|thumb|upright=1.2|[[BNSF Railway]] freight service in the United States|alt=Orange locomotive hauling freight]]
[[File:DeutscheBahn gobeirne.jpg|thumb|upright=1.2|German [[InterCityExpress]] (ICE)|alt=Sleek white passenger train at a station]]
Rail transport is an energy-efficient<ref>{{cite web |url=http://www.progressiverailroading.com/news/article.asp?id=16740 |title=Railroad Fuel Efficiency Sets New Record |author=American Association of Railroads |accessdate=12 April 2009}}</ref> but [[capital intensive|capital-intensive]], means of mechanized land transport. The tracks provide smooth and hard surfaces on which the wheels of the train can roll with a minimum of [[friction]]. Moving a vehicle on and/or through a medium (land, sea, or air) requires overcoming [[Friction|resistance]] to motion. A land vehicle's total resistance (in [[Pound (mass)|pounds]] or [[Newtons]]) is a [[quadratic function]] of the vehicle's speed:
 
:<math>\qquad\qquad R = a + bv + cv^2 </math>
 
where:
:''R'' denotes total resistance
:''a'' denotes initial constant resistance
:''b'' denotes velocity-related constant
:''c'' denotes constant that is function of shape, frontal area, and sides of vehicle
:''v'' denotes velocity
:''v''<sup>2</sup> denotes velocity, squared<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
Essentially, resistance differs between vehicle's contact point and surface of roadway. Metal wheels on metal rails have a significant advantage of overcoming resistance compared to rubber-tired wheels on any road surface (railway – 0.001g at {{convert|10|mph}} and 0.024g at {{convert|60|mph}}; truck – 0.009g at {{convert|10|mph}} and 0.090 at {{convert|60|mph}}). In terms of cargo capacity combining speed and size being moved in a day:
 
* human – can carry {{convert|100|lbs}} for {{convert|20|mi}} per day, or 1 [[Units of transportation measurement#Payload-Distance|tmi]]/day (1.5 [[Units of transportation measurement#Payload-Distance|tkm]]/day)
* horse and wheelbarrow – can carry 4 tmi/day (5.8 tkm/day)
* horse cart on good pavement – can carry 10 tmi/day (14 tkm/day)
* fully utility truck – can carry 20,000 tmi/day (29,000 tkm/day) {{citation needed|date=July 2012}}
* long-haul train – can carry 500,000 tmi/day (730,000 tkm/day)<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/> Most trains take 250–400 trucks off the road, thus making the road more safe.
 
In terms of the horsepower to weight ratio, a slow-moving barge requires {{convert|0.2|hp/ST}}, a railway and pipeline requires {{convert|2.5|hp/ST}}, and truck requires {{convert|10|hp/ST}}. However, at higher speeds, a railway overcomes the barge and proves most economical.<ref name="AREMA. 2003. Practical Guide to Railway Engineering"/>
 
As an example, a typical modern wagon can hold up to {{convert|113|t|ST}} of freight on two four-wheel [[bogie]]s. The track distributes the weight of the train evenly, allowing significantly greater loads per [[axle]] and wheel than in road transport, leading to less wear and tear on the permanent way. This can save energy compared with other forms of transport, such as road transport, which depends on the friction between rubber tires and the road. Trains have a small frontal area in relation to the load they are carrying, which reduces [[air resistance]] and thus energy usage.
 
In addition, the presence of track guiding the wheels allows for very long trains to be pulled by one or a few engines and driven by a single operator, even around curves, which allows for [[economies of scale]] in both manpower and energy use; by contrast, in road transport, more than two [[Articulated vehicle|articulations]] causes [[fishtailing]] and makes the vehicle unsafe.
 
===Usage===
Due to these benefits, rail transport is a major form of passenger and freight transport in many countries. It is ubiquitous in Europe, with an integrated network covering virtually the whole continent. In India, China, South Korea and Japan, many millions use trains as regular transport. Freight rail transport is widespread and heavily used in North America, but intercity passenger rail transport on that continent is relatively scarce outside the [[Northeast Corridor]] due to the loss of competition to other preferred modes, particularly automobiles and airplanes.<ref name="EuDaly, K, et al. 2009. Complete Book of North American Railroading"/><ref name="APTA stats">{{cite web| url=http://www.apta.com/research/stats/ridership/| title=Public Transportation Ridership Statistics| publisher=American Public Transportation Association| year=2007| accessdate=10 September 2007 |archiveurl = http://web.archive.org/web/20070815101950/http://www.apta.com/research/stats/ridership/ <!-- Bot retrieved archive --> |archivedate = 15 August 2007}}</ref>
[[File:WAP-7 class electric locomotive of Indian Railways.jpg|thumb|left|[[Indian locomotive class WAP-7|WAP 7]] locomotive in India]]
[[File:NZB-Kacheguda Passenger with WDG-3A loco 02.jpg|thumb|left|'''Indian locomotive class WDG-3A''' one of the high power locomotives in India]]
Africa and South America have some extensive networks such as in South Africa, Northern Africa and Argentina but some railways on these continents are isolated lines. Australia has a generally sparse network befitting its population density but has some areas with significant networks, especially in the southeast. In addition to the previously existing east-west transcontinental line in Australia, a line from north to south has been constructed. The highest railway in the world is the [[Qingzang railway|line to Lhasa]], in Tibet,<ref>{{Cite news|publisher=Xinhua News Agency|date=24 August 2005|url=http://news.xinhuanet.com/english/2005-08/24/content_3397297.htm|title=New height of world's railway born in Tibet|accessdate=8 May 2011}}</ref> partly running over permafrost territory. The western Europe region has the highest railway density in the world and has many individual trains which operate through several countries despite technical and organizational differences in each national network.
 
===Social and economic benefits===
[[File:JRE-TEC-E5 omiya.JPG|thumb|[[Japan]]ese [[Shinkansen]]]]
Railways have also been shown to contribute to social vibrancy and economic competitiveness in its ability to transport large amounts of customers and workers to [[city center]]s and [[inner suburbs]] (i.e. [[Washington DC]] as a cultural/policy center due to [[Washington Metro|Metrorail]] system, [[San Francisco]]'s lively downtown due to the [[BART]] system{{citation needed|date=April 2013}}). [[Hong Kong]] has recognized rail as "the backbone of the [[public transit system]]" and as such developed their franchised bus system and road infrastructure in compherensive alignment with their rail services.<ref>Hong Kong Information Services Department of the Hong Kong SAR Government. Hong Kong 2009</ref> China's large cities such as [[Beijing]], [[Shanghai]], and [[Guangzhou]] recognize rail transit lines as the framework and bus lines as the main body to their metropolitan transportation systems.<ref>Hau H., Yun-feng G., Zhi-gang, L., Xiao-guang, Y. (2010). Effect of Integrated Multi-Modal Transit Information on Modal Shift. Intelligent Transportation Systems (ITSC), 2010 13th International IEEE Conference. 1753-1757pg.</ref> The Japanese [[Shinkansen]] was built to meet the growing traffic demand in the "heart of Japan's industry and economy" situated on the [[Tokyo]]-[[Kobe]] line.<ref>Nishida, M., The Shinkansen High-Speed Rail Network of Japan. Proceedings of an IIASA Conference, June 27–30, 1977.</ref>
 
[[File:Bundesarchiv Bild 146-1994-022-19A, Mobilmachung, Truppentransport mit der Bahn.jpg|thumb|right|German soldiers in a railway [[Passenger car (rail)|car]] on the way to the front in August 1914. The message on the car reads '''Von München über Metz nach Paris'''. (From Munich via Metz to Paris).]] During much of the 20th Century rail was an invaluable element of military [[mobilization]], allowing for the quick and efficient transport of large numbers of reservists to their mustering-points, and infantry soldiers to the front lines. However, by the 21st Century, rail transport - limited to locations on the same continent, and vulnerable to air attack - had largely been displaced by the adoption of [[Airlift|aerial transport]].
 
As opposed to [[highway]] expansion, indicative of the U.S. transportation policy, that incentivizes development of [[suburbs]] at the periphery, contributing to increased [[vehicle miles traveled]], [[carbon emissions]], development of [[greenfield land|greenfield]] spaces, and depletion of [[natural reserve]]s, railways channel growth toward dense city [[agglomerations]] and along its artery. These arrangements revalue city spaces, local [[taxes]], [[house|housing]] values, and promotion of [[mixed use development]].<ref>Squires, G. Ed. (2002) Urban Sprawl: Causes, Consequences, & Policy Responses. The Urban Institute Press.</ref><ref>Puentes, R. (2008). A Bridge to Somewhere: Rethinking American Transportation for the 21st Century. Brookings Institution Metropolitan Policy Report: Blueprint for American Prosperity series report.</ref>
 
== See also ==
{{Portal|Trains}}
* [[Environmental design in rail transportation]]
* [[International Union of Railways]]
* [[List of rail transport topics]]
* [[List of railroad-related periodicals]]
* [[List of railway companies]]
* [[Mega project]]
* [[Mine railway]]
* [[Passenger rail terminology]]
* [[Rail transport by country]]
* [[Railway systems engineering]]
* [[Taiwanese push car railways]]
 
==References==
{{Reflist|30em}}
 
==Notes==
{{reflist|group=Nb}}
 
==External links==
* {{Wikiquote-inline}}
* {{commons-inline|Railroad}}
* {{Wiktionary-inline|railway}}
* {{Wikivoyage-inline|Rail travel}}
 
{{Public transport}}
{{Railway track layouts}}
{{Rail tracks}}
{{Use dmy dates|date=February 2011}}
 
{{DEFAULTSORT:Rail Transport}}
[[Category:Rail transport| ]]
[[Category:Trains]]
 
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Latest revision as of 23:26, 7 January 2015

My name is Pansy (46 years old) and my hobbies are Origami and Baton twirling.

my homepage ... tenali.org [Read Significantly more]