Breckland Forest is an 18,126 hectare biological and geological Site of Special Scientific Interest in many separate areas between Swaffham in Norfolk and Bury St Edmunds in Suffolk. It is part of the Breckland Special Protection Area under the European Union Directive on the Conservation of Wild Birds. It contains two Geological Conservation Review sites, Beeches Pit, Icklingham and High Lodge. Barton Mills Valley is a Local Nature Reserve in the south-west corner of the site.