Tumulus of Bougon

The Tumulus of Bougon or Necropolis of Bougon (French: "Tumulus de Bougon", "Nécropole de Bougon") is a group of five Neolithic barrows located in Bougon near La-Mothe-Saint-Héray, between Exoudon and Pamproux in Poitou-Charentes, France. Their discovery in 1840 raised great scientific interest. To protect the monuments, the site was acquired by the department of Deux-Sèvres in 1873. Excavations resumed in the late 1960s. The oldest structures of this prehistoric monument date to 4800 BC.

The site is located on a limestone plateau within a loop of the river Bougon. The area used to be known as "Les Chirons".

The stepped mound, erected in the early 4th millennium BC, has a diameter of 42 m and a maximum height of 5 m. Its large rectangular chamber (7.8 x 5 m, 2.25 m high) lies south of its centre. It is connected by a non-centrally placed passage. There is evidence that the passage was still used by the 3rd millennium BC. The chamber's walls contain artificially shaped orthostats, the gaps were filled with dry stone walling. The chamber is covered by a capstone which weighs 90 tons. It is supported by two monolithic pillars, which also serve to subdivide the chamber.

During its excavation in 1840, about 200 skeletons were discovered in three layers, separated by stone slabs. The vague reports of that early excavation prevent any detailed chronological analysis. Accompanying finds included flat-bottomed and round-bottomed pottery, beads, pierced teeth, chains of seashells and stone tools, including a diorite mace. More recent excavations showed that the grave was abandoned shortly after its construction. The passage had been blocked with a large stone slab. At its base lay the skull of a man who had undergone three trepanations during his lifetime. Pottery was also found in front of the monument's facade, suggesting that cult activities, entailing the deposition of pottery, took place after its closure. About 1,000 years later, the monument was re-used for more burials by people of a different culture who reached the passage from above.

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