Speed on rails began with a problem of weight. On 21 February 1804 the world's first railway journey, with a steam locomotive built by Richard Trevithick, ran in south Wales. The locomotive weighed about five tons and was so heavy that it broke the cast-iron rails it ran on.

A steam locomotive burns coal as its fuel, and the heat of the fire turns the water in a boiler into steam, and high-pressure steam goes into cylinders and pushes pistons back and forth. The chuff-chuff sound is the sound of used steam escaping and leaving through the chimney.

The Rainhill Trials of October 1829 lasted nine days, with more than 10,000 people coming to watch the locomotives. Each had to make ten return trips along a specially built track about 1.5 miles (2.4 km) long. The judges did not pick a winner on speed alone. They also weighed how reliable each locomotive was and how much fuel and water it used.

The engine Novelty ran faster than Rocket but broke down and could not finish, whereas Robert Stephenson's Rocket won the Rainhill Trials in 1829 and was used on the Liverpool and Manchester Railway, reaching speeds of at least 30 miles per hour (48 km/h).

As of November 2026, the record for a train running on steel wheels on rails is 574.8 km/h. A specially modified French TGV train called V150 reached it on 3 April 2007.

A maglev train floats above its track, lifted by the force of electromagnetism. At speed, Japan's SCMaglev does not touch the track: magnetic force between its superconducting magnets and coils on the ground lifts it about 10 centimetres (4 inches).

The on-board superconducting magnets of Japan's SCMaglev use niobium-titanium wire cooled with liquid helium.

As of November 2026, the fastest speed ever recorded for a maglev train is 603 km/h (374 mph). The Japanese L0 Series reached it on a test track in Yamanashi, Japan, in April 2015.

Words to know

• locomotive: pulling engine
• pistons: steam plungers
• reliable: works without failing
• maglev: floating train