West Yatton Down

West Yatton Down is a 14.4 hectare biological Site of Special Scientific Interest in Wiltshire, notified in 1971.
The site is an example of unimproved limestone grassland. Among the more notable plants species are bastard-toadflax, Dyer's greenweed, and musk orchid. Other species present include yellow-wort, kidney vetch, devil's-bit scabious, bee orchid, tor-grass and upright brome.
The site is also of interest for invertebrates. Twenty-five butterfly species have been recorded, including chalkhill blue, Duke of Burgundy, pearl-bordered fritillary and green hairstreak.