The Mên-an-Tol is a small formation of standing stones near the Madron-Morvah road in the Penwith area of Cornwall, United Kingdom (grid reference SW426349). It is about 3 miles north west of Madron. It is also known locally as the "Crick Stone".

It consists of three upright granite stones: a wide stone with its middle holed out with two cuboid stones to each side, in front of and behind the hole. When seen at an angle from one side, the stones form a three-dimensional "101".

These stones might have been the entrance to some now vanished tomb. It is possible that they were part of some ancient calendar.

Mên-an-Tol is supposed to have a fairy or pixy guardian who can make miraculous cures. In one case a Changeling baby was put through the stone in order for the mother to get the real child back. Evil pixies had changed her child and the ancient stones were able to reverse their evil spell.

Local legend claims that if at full moon a woman passes through the holed stone seven times backwards, she will soon become pregnant.

Another legend is that passage through the stone will cure a child of rickets (osteomalacia). For centuries, children with rickets were passed naked through the hole in the middle stone nine times. Its curative powers actually are reflected in its name.

The circular stone aligns exactly with the centre stone at Boscawen-Un and the church at nearby St Buryan. While this may conceivably be coincidental, the precision of the alignment suggests an intentional positioning of the structures in relation to each other.