A particularly imposing monument. The structures of this type are located in the Carnac area. The best-known example is the Mont Saint-Michel tumulus, measuring 125 metres by 60 metres, and standing 10 metres high. These imposing masses consist of a central core of stones covered with a layer of clay and with more stone piled on top. They covered closed graves (cists) in which deposits of polished axe-heads and jewellery items were found.
