BELIEFS × SOCIETY × TECHNOLOGY

The First Megaliths, in Brittany

~4700 BCE

Neolithic · Neolithic · Holocene · Northgrippian

Megalithic monuments are tombs, standing stones, circles and alignments raised from large stone slabs, clustered along the Atlantic coasts of Europe and around the Mediterranean. Schulz Paulsson modelled 2,410 radiocarbon dates from megalithic, premegalithic and contemporaneous non-megalithic contexts to settle a hundred-year-old question: whether the idea travelled from one source or arose on its own in several regions. The oldest graves, small closed chambers of stone slabs under a mound of earth or stone, appear in the second half of the fifth millennium BCE in northwest France, the Channel Islands, Catalonia, Corsica and Sardinia, within a window most probably 200 to 300 years wide. Northwest France alone has monumental graves that predate the megaliths and forms transitional to them, which is the ground for treating it as the region of origin; at Carnac, the first building phase of the great tumulus falls between 4782 and 4594 BCE.

Why it matters

Spread along a coast within a few centuries implies boats able to carry people and ideas between regions no land route connects, and Schulz Paulsson reads the dates as evidence for seafaring rather than for a slowly advancing frontier. The monuments also say who lay inside them: genomes from five megalithic sites show close kin buried within a single tomb, and in Ireland between tombs, with the same male lines recurring, which the authors read as patrilineal kindred groups.

Dating & uncertainty

The date kept here, about 4700 BCE, is the middle of the interval obtained for the first building phase of the Carnac tumulus, 4782 to 4594 BCE. The earliest megalithic chambers in Brittany fall within that horizon but carry no radiocarbon dates of their own: they are placed by their grave goods, whose contexts run from 4794 to 3999 BCE. What hangs on the bracket, 6,800 to 6,500 years before present, is the direction of travel, since northwest France is held to be the region of origin only because it alone shows monumental graves before the megaliths.

Sources

1. Schulz Paulsson (2019), Proceedings of the National Academy of Sciences · Radiocarbon dates and Bayesian modeling support maritime diffusion model for megaliths in Europedoi:10.1073/pnas.1813268116
2. Blanchard et al. (2025), Antiquity · Le Plasker in Plouharnel (fifth millennium cal BC): a newly discovered section of the megalithic complex of Carnacdoi:10.15184/aqy.2025.10123
3. Sánchez-Quinto et al. (2019), Proceedings of the National Academy of Sciences · Megalithic tombs in western and northern Neolithic Europe were linked to a kindred societydoi:10.1073/pnas.1818037116

Our species’ history as one day

23:29:2230 min 38 s before midnight

if the 315,000 years of Homo sapiens were compressed into a single day