Pen-y-crug is a hill in the Brecon Beacons National Park in the county of Powys, south Wales.
Its flat trig point adorned summit at 331m overlooks the valley of the River Usk to the south.
A small car park off the minor road to its north provides a convenient starting point for many walkers.
The summit is crowned by an impressive Iron Age hillfort, one of several in the Usk Valley.
[3] There are the remains of a brick and tile works dating from Victorian times on its southeastern flank.