12m high, 125m long and 60m wide, the tumulus was built c. 4 500 BC. A dolmen, two burial chambers, fifteen or so stone chests filled with bones and a large number of axes, potteries and jewellery were found under this pile of earth and stones. They are now on display in the Prehistoric History Museum.
An orientation table has been set up on the Tumulus. This is an outstanding viewpoint with superb 360° panoramic views from Groix to the Rhuys Peninsula, including Quiberon Bay, Houat, Hoëdic and the surrounding countryside.
