Running, for approximately 8 miles, from Llangollen to the current western terminus at Carrog, this railway is the only operational standard gauge heritage line in North Wales. For most of its length it follows the course of the River Dee affording excellent views of the dramatic Welsh countryside many of which are not available to travellers on the main A5 road which also follows the route higher up the valley side.
In its previous life it formed part of a main route linking Ruabon with the coastal line at Barmouth. The line led a relatively quiet life but did not open up to tourists and in its early days made a number of small slate quarries viable concerns.