Crazywell Pool or Crazy Well Pool is a large pond situated about 3 km south of Princetown just off the path between Burrator and Whiteworks on the western side of Dartmoor, Devon, England at grid reference SX582705. It is about 100 metres long and has a surface area of about 3,500 square metres.
The pool is thought to be the result of excavations by tin miners, and is either a flooded mine shaft, or a reservoir. The presence of tin workings downhill from the pool support this view. The valley of has been extensively worked with many mining remains along its short length. The level of the pool never varies much from its mean—it is maintained by a hidden spring and by subterranean drainage at its lower end. Near to the pool is Crazywell Cross, one of the line of crosses that marked the ancient track between Buckfast Abbey and Tavistock Abbey.
Wikipedia https://en.wikipedia.org/wiki/Crazywell_Pool
Coordinates 50°30'59.977" N -4°0'2.587" E