Black Down | |
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A view across Black Down from Beacon Batch in the Mendip Hills
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Highest point | |
Elevation | 325 m (1,066 ft) |
Prominence | c. 241 m |
Parent peak | Dunkery Beacon |
Listing | Marilyn |
Geography | |
Location | Mendip Hills, England |
OS grid | ST484572 |
Topo map | OS Landranger 141 |
Black Down is the highest hill in the Mendip Hills, Somerset, in south-western England. Black Down lies just a few miles eastward of the Bristol Channel at Weston-super-Mare, and provides a view over the Chew Valley. The summit is marked with an Ordnance Survey trig point, the base of which has been rebuilt by the Mendip Hills AONB authority.
The shortest route of ascent goes from the Burrington Combe car park and is approximately 1 km long.
Black Down is an open-access area mostly consisting of moors, with dense cover of associated vegetation such as heather and bracken. According to a local organization's newsletter, the name "Black Down" comes from the Saxon word 'Blac' or 'Bloec' meaning bleak, 'Dun' meaning down or fort.
The rocks form an anticline with the oldest being Old Red Sandstone at the summit, which was deposited during the Devonian period between 400 and 362 million years ago, with younger Portishead Beds of limestone and Black Nore Sandstone on either side. As a result of the Variscan mountain-building, the Mendip area now comprises at least four anticlinal fold structures, with an east-west trend, each with a core of older Devonian sandstone and Silurian volcanic rocks. The Devonian and Silurian rocks are generally more resistant to weathering than the limestone, and form some of the highest points on the hills, including the highest at Black Down, 325 metres (1068 ft) above sea level. Black Down is a moorland area, with its steeper slopes covered in bracken (Pteridium) and its flatter summit in heather (Calluna) and grasses rather than the pasture which covers much of the plateau.