This is one of Brittany's fine Megalithic monuments. It was erected in purple-coloured schist and made up of 42 stones, of which half a dozen weigh between 40 and 45 tons each. It includes a monumental entrance, a portico followed by a low corridor, leading to a vast, partitioned chamber. This Megalithic site seems to have been laid out in the Middle Neolithic Age (4000 B.C.). Research has shown that the stones were moved over nearly 4 km, which was a real achievement in those days.