Engineering
The aim of the project was to turn the remaining sections of the 9 1/2
mile Penydarren tramroad into the Trevithick’s Trail, a public cycle path
between Merthyr and Abercynon.
The original tramroad was completed in 1802, and was in use until 1875.
It's ownership was shared by the Dowlais, Penydarren and Plymouth ironworks
and ran from Merthyr to Abercynon Much of the existing tramroad could be
followed but was overgrown in most places with no appropriate surface to
walk or cycle.

Original stone sleepers were found along parts of the trail which carried
the iron rails. The tramway was used as part of a bet between the iron
masters to see whether a load of 10 tons of iron could be transported using
a steam engine along the tramway to Abercynon on rails.
The bet was won and Richard Trevithick’s Worlds First Steam Locomotive
hauled 10 tons of iron, 5 wagons and 70 men along the Merthyr Tydfil
Tramroad from Penydarren to Abercynon on 21st February 1804.
Alun Griffiths Ltd were the main contractor who carried out the work on
the path under the supervision of Mark Robinson and Carwyn Morris, engineers
for Merthyr Tydfil Council and also main designers of the scheme.