Dowrog Common Nature Reserve, owned by the National Trust, and managed by the Wildlife Trust West Wales, formerly the Dyfed Wildlife Trust, is the largest and most diverse of a series of almost treeless lowland heaths on the St Davids Peninsula. Some 101ha in extent, Dowrog is joined to the south-west by Waun Fawr (16ha) and to the north-east by Tretio Common (55ha).