Railroad. Rail transport is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prepared flat surface, rail vehicles are directionally guided by the tracks on which they run. Tracks usually consist of steel rails. Rolling stock in a rail transport system generally encounters lower frictional resistance than rubber-tyred road vehicles, so passenger and freight cars can be coupled into longer trains. The operation is carried out by a railway company, providing transport between train stations or freight customer facilities. Power is provided by locomotives which either draw electric power from a railway electrification system or produce their own power, usually by diesel engines or, historically, steam engines. Most tracks are accompanied by a signalling system. Railways are a safe land transport system when compared to other forms of transport. Railway transport is capable of high levels of passenger and cargo use and energy efficiency, but is often less flexible and more capital-intensive than road transport, when lower traffic levels are considered. The oldest known, man/animal-hauled railways date back to the 6th century BC in Corinth, Greece. Rail transport resumed in mid 16th century in Germany in the form of horse-powered funiculars and wagonways. Modern rail transport began with a British steam locomotive in 1802. The Locomotion No. 1 became the first steam locomotive to carry passengers on a public rail line, the Stockton and Darlington Railway in 1825, and the first public inter-city railway line, the Liverpool and Manchester Railway, opened in 1830. Steam engines brought mainline railways, a key component of the Industrial Revolution. Shipping cost less, and fewer goods were lost, than in water transport. The change from canals to railways allowed for "national markets" in which prices varied little from city to city. The use of railway timetables led to standard railway time replacing local mean time. The invention and development of the railway in the United Kingdom was one of the most important technological inventions of the 19th century. The world's first underground railway, the Metropolitan Railway, opened in 1863. In the 1880s, railway electrification began with tramways and rapid transit systems. Starting during the 1940s, steam locomotives were replaced by diesel locomotives, with steam becoming rare by the 2000s. During the 1960s, electrified high-speed railway systems were introduced in Japan and later in some other countries. Many countries are in the process of replacing diesel locomotives with electric locomotives, mainly due to environmental concerns, as in Switzerland, which has completely electrified its network. Guided ground transport outside the traditional railway definitions, such as monorail or maglev, have been tried but have seen limited use. Following a decline after World War II due to competition from cars and airplanes, rail transport has had a revival in recent decades due to road congestion and rising fuel prices, as well as governments investing in rail as a means of reducing CO2 emissions in the context of concerns about global warming. Smooth, durable road surfaces have been made for wheeled vehicles since prehistoric times. In some cases, they were narrow and in pairs to support only the wheels. That is, they were wagonways or tracks. Some had grooves or flanges or other mechanical means to keep the wheels on track. For example, evidence indicates that a 6 to 8.5 km long Diolkos paved trackway transported boats across the Isthmus of Corinth in Greece from around 600 BC. The Diolkos was in use for over 650 years, until at least the 1st century AD. Paved trackways were also later built in Roman Egypt. In 1515, Cardinal Matthäus Lang wrote a description of the Reisszug, a funicular railway at the Hohensalzburg Fortress in Austria. The line originally used wooden rails and a hemp haulage rope and was operated by human or animal power, through a treadwheel. The line still exists and is operational, although in updated form and is possibly the oldest operational railway. Wagonways using wooden rails, hauled by horses, started appearing in the 1550s to facilitate the transport of ore tubs to and from mines and soon became popular in Europe. Such an operation was illustrated in Germany in 1556 by Georgius Agricola in his work De re metallica. This line used "Hund" carts with unflanged wheels running on wooden planks and a vertical pin on the truck fitting into the gap between the planks to keep it going the right way. The miners called the wagons Hunde from the noise they made on the tracks. There are many references to their use in central Europe in the 16th century. Such a transport system was later used by German miners at Caldbeck, Cumbria, England, perhaps from the 1560s. A wagonway was built at Prescot, near Liverpool, sometime around 1600, possibly as early as 1594. Owned by Philip Layton, the line carried coal from a pit near Prescot Hall to a terminus about one-half mile away. A funicular railway was also made at Broseley in Shropshire some time before 1604. This carried coal for James Clifford from his mines down to the River Severn to be loaded onto barges and carried to riverside towns. The Wollaton Wagonway, completed in 1604 by Huntingdon Beaumont, has sometimes erroneously been cited as the earliest British railway. It ran from Strelley to Wollaton near Nottingham. The Middleton Railway in Leeds, which was built in 1758, later became the world's oldest operational railway, albeit now in an upgraded form. In 1764, the first railway in the Americas was built in Lewiston, New York.