Pen Cerrig-calch

Pen Cerrig-calch is a mountain summit in the Black Mountains that rises to 701 meters (2,300 feet) above sea level. From the top, walkers can see across the Usk Valley and toward the Brecon Beacons to the north.

An Iron Age hillfort called Crug Hywel once stood on the southeastern spur, dating back roughly 2,000 years. This settlement reveals that the area has drawn people seeking shelter and high vantage points for many centuries.

The Welsh name translates to 'top of the limestone rock', reflecting the geological composition that differs from the surrounding Old Red Sandstone landscape.

The southeast approach starting from Crug Hywel is the most common walking route to the summit. Several paths connect the Usk Valley with the Grwyne Fechan valley to the east, giving visitors different ways to reach the top.

The southwestern slope features a striking cliff called Darren, which was created by a massive landslip in the early post-glacial period. This distinctive rock face stands as a visible reminder of how dramatically the landscape shifted after the ice age.