The 15.2 kilometre Trevithick Trail commemorates the first journey by a steam locomotive to pull a load on rails in 1804, the precursor of the Railway Age which changed the world in the 19th century.

By the beginning of the 1800s Merthyr Tydfil was developing from a rural community into the Iron Capital of the World with its four iron works at Cyfarthfa, Dowlais, Penydarren and Plymouth.

It would continue to grow and by the middle of the century became the largest town in Wales with a population of more than 50,000 inhabitants as the four great iron works continued to expand.

On February 21, 1804, the Penydarren locomotive, designed and built by the Cornish inventor Richard Trevithick, pulled a load of 10 tons of iron and 70 men nine miles down the Taff Valley - all for a bet.

The historic journey went from the Penydarren works to the Navigation where it joined the Glamorgan Canal so linking the industrial heart of Merthyr Tydfil with the port of Cardiff and the rest of the world.

Along the trail markers point out the historical significance of various locations as you follow the track along the nine-mile route.