This is one of hundreds of rocky outcrops on Dartmoor known as 'Tors'.
Cox Tor is not particularly high at only 442m but it is easily accessible being only a 5 minute walk from the main road. There are good views over Plymouth and into Cornwall, and on the north-east facing slopes there are remains of an ancient settlement.

Cox Tor on Dartmoor - Dartmoor visitor guide showing a virtual tour of 'Cox Tor on Dartmoor' linked to an interactive map with local and travel information. 360° panoramas from Devon.