| Hatterrall Hill | |
|---|---|
 Hatterrall Hill viewed from the east | |
| Highest point | |
| Elevation | 531 m (1,742 ft) |
| Prominence | 44 m (144 ft)  |
| Parent peak | Black Mountain |
| Coordinates | 51°55′32″N 3°00′26″W / 51.9256°N 3.0071°W |
| Geography | |
  Hatterrall Hill  Hatterrall Hill Hatterrall Hill (England)  Hatterrall Hill Hatterrall Hill (the United Kingdom) | |
| Parent range | Black Mountains |
| OS grid | SO308256 |
Hatterrall Hill (Welsh: Mynydd Y Gader) is a rounded peak in the Black Mountains which sits on the Wales-England border, partly in Monmouthshire, Wales and partly in Herefordshire, England. Its summit at 531m is the high point of a peaty plateau which falls away steeply on all sides. Broad ridges run to the north, the southeast and southwest. To the north the ridge (known as Hatterrall Ridge) dips to a col at around 485m elevation before rising gradually over several kilometres towards Crib y Garth / Black Hill and Hay Bluff. The ridge to the southwest ends abruptly at the sheer cliff known as the Darren below which is a considerable landslip area extending south to the hamlet of Cwmyoy with its mis-shapen church. The Welsh part of the hill falls within the Brecon Beacons National Park.