The reserve consists of a disused quarry with two main faces. It is one of the few sites in the county showing good exposures of andesite lava. The lower face is variable andesite-dacite and the upper mainly purple porphyritic andesite with amygdaloidal patches.
The floor of the lower bench contains gorse, elder, hawthorn and broom scrub with elm and ash. The upper bench supports grazed bentfescue grassland. On the quarry faces grow polypody fern, common stork's-bill, dove's-foot crane's-bill, harebell and bluebell. The quarry faces north and is locally wet - these factors may be responsible for the good bryophyte and lichen flora. The site is managed in partnership with Ford and Etal Estates.