Arms Tor is one of the western Dartmoor outcrops that gives a lot back for a relatively short effort. It rises above Lydford and the open moor, close to better-known Brat Tor, with granite stacks that look especially strong when approached across High Down.
The climb is steep enough to feel earned, but it is not an expedition in settled weather. Go for the views, the moorland texture, and the chance to link several tors into a circular walk. As always on Dartmoor, carry a map, watch the weather, and do not treat a short distance as a guarantee of easy navigation.