The local rocks are sedimentary shales and mudstones with some Silurian limestone.

With a height of 660 metres (2,170 ft), it is the highest point in the Radnor Forest and the historic county top of Radnorshire.

The summit is located on a broad heathery plateau, which is separated from Black Mixen: the eastern plateau summit, by the cwm of Harvey Dingle.

To the west is Drygarn Fawr and Gorllwyn, to the northwest Plynlimon, to the north Beacon Hill and the Clun Forest (Shropshire), and to the south the Black Mountains.

You can help Wikipedia by expanding it.This article about a Site of Special Scientific Interest is a stub.