Megalithic landscapes of Carnac and South Morbihan

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Saint-Michel tumulus

This major megalithic monument in southern Morbihan stands above the town of Carnac, with St Michel’s chapel now standing on its summit. 

The tumulus was built during the fifth millennium BC. Excavations conducted in the late nineteenth century by René and Louis Galles uncovered a central chamber in which a few fragments of bones and coals were found, along with a number of valuable objects: jadeite axes and variscite jewellery sets. In the early twentieth century, Zacharie Le Rouzic undertook fresh research leading to the discovery of small peripheral chests around the central chamber, as well as a corridor dolmen, added in a later phase, at the eastern end of the tumulus. The monument features elaborate architecture: the burial chambers were covered with a pile of rubble, which in turn was covered with a layer of earth and stones; the whole structure was enclosed in a thick layer of waterlogged silt, used to seal the inner burial structures. The objects found during these excavations – axes, pearls and flint tools – are now preserved at the Carnac and Vannes Polymathique museums.

The dimensions (125m long, 60m wide and 10m high), architecture and valuable objects contained in the St Michel tumulus make it characteristic of the great tumuli of southern Morbihan.

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This site belongs to and is run by Centre des Monuments Nationaux. Public access is strictly prohibited during the work in progress.