Hatterrall Ridge

The Hatterrall Ridge (sometimes spelled Hatterall) is a ridge in the Black Mountains forming the border between Powys and Monmouthshire in Wales and Herefordshire in England. The ridge is about 10 miles (16 km) long, and is followed by the Offa's Dyke Path. On the west side of the ridge is the Vale of Ewyas, and on the east side is the Olchon Valley and Black Hill. The western side of the ridge falls within the Brecon Beacons National Park. Much of the northern part of the ridge is a broad whaleback, but it narrows down considerably further south, and especially near to Llanthony Priory in the Vale of Ewyas to the west of the mountain. There is a large and prominent landslip on the eastern side of the mountain here, known as Black Darren, where a large slice of the rocks has fallen away from the main mass of the hill.

The ridge to the southwest ends abruptly at the sheer cliff known as the Darren below which is a considerable landslipped area extending south to the hamlet of Cwmyoy with its mis-shapen church.

The highest point on the ridge is Black Mountain (elevation 2306 feet or 703 m), near its northern end. Hatterrall Hill (elevation 1742 feet or 531 m) is near the southern end of the ridge. The path is surrounded by peat and often wet underfoot off the footpath, which itself has a dry stony surface. Lower parts of the ridge towards then south end are grass and heath covered, and generally drier than the high moorland. Since much of the ridge is unfenced common land, Welsh ponies and sheep can graze over large parts of the mountain.

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