This road up into the Cambrian Mountains from the town of Rhayader is steep, narrow and winding but the scenery at the top is worth it. The Cambrian Mountains is a barren and sparsely populated wilderness, covering parts of Radnorshire and Ceredigion, which includes the sources of the River Severn and River Wye and the highest point of the range is Plynlimon at 2,467 feet.

Near the top of the road from Rhayader is this nice little waterfall and there is space to stop and look. The geology of this area consists of Ordovician and Silurian sandstones and mudstones which in many areas outcrop only infrequently so resulting in more rounded grassy hills.

This shows a small part of the Craig Goch Reservoir which is the highest of the reservoirs in the Elan Valley group. There is a turning a short distance away which goes further into the Elan Valley Reservoirs area.

The landscape here has been much modified by a series of ice ages which started around 2.4 million years ago and the most recent ended only 12,000 years ago. The Cambrian Mountains appear as a dissected plateau broken only by glacial gouging and by the deep clefts of the river valleys.

This road leads, through the village of Cwmystwyth, to Devil's Bridge and, as you can no doubt see, the scenery on this route is spectacular.

On the western edge of the Cambrian Mountains, in the village of Pontrhydfendigaid, is Strata Florida Abbey.

This Cistercian abbey was the centre of a large mountain estate. Paths would have been established based on the requirements of visiting pilgrims, the need for monks from the abbey to travel to chapelries and the outlying granges. Many of these paths would have been in use previously, and later the long distance cross-country routes became drove roads.