Two huge chunks of millstone grit with a recumbent boulder forming a natural 'altar' and enclosing niche. The Thimble Stones lay on the path that runs along the boundary wall between Ashlar Chair and the radio masts at Whetstone Gate. Nearby to the south are the Two Eggs.
It is quite likely that these stones had some relevance to the prehistoric inhabitants of the moor although the 'cups' are most likely the result of weather erosion.
I visited the stones on Halloween and was caught in a hailstorm whilst there... the place was just buzzin'!!