Broadmoor to Bagshot Woods and Heaths (grid reference SU877644) is a 4,200 hectares (10,400 acres) biological Site of Special Scientific Interest (notified in 1973) in Berkshire and Surrey.
One feature of note within the site is an Iron Age hill fort called Caesar's Camp.
References
Broadmoor to Bagshot Woods and Heaths Wikipedia(Text) CC BY-SA