Cairn de Gavrinis

One of the most special neolithic ruins along the Morbihan coast, this giant cairn is out on the island of the same name. Dating from 4000 BCE and measuring more than 50m in diameter, the beautifully situated tomb is well-known for its profusion of intricate engravings. You access the site on a 15-minute boat trip from the harbor at Larmor-Baden (15km southeast of Auray) and the visit is guided. Reserve tickets in advance online.