The summit is marked with an Ordnance Survey trig point, the base of which has been rebuilt by the Mendip Hills AONB authority.

Black Down is an open-access area mostly consisting of moors, with dense cover of associated vegetation such as heather and bracken.

[4] 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.

It was laid out by Shepperton Film Studios, based on aerial photographs of the city's railway marshalling yards.

Drums of oil were also ignited to simulate the effect of a blazing city or town, with the aim of fooling subsequent waves of bombers into dropping their bombs on the wrong location.