Timeline

Heritage classified

Key figures

Origin and history

The Dolmen du Riholo is a megalithic monument located in Herbignac, in the Pays de la Loire. It stands on a dominant wetland promontory on the northern edge of the Brière. This dolmen belongs to a rare architectural category, called transept or transept tombs, characteristic of the two banks of the Loire estuary. These buildings are distinguished by a central gangway leading to a master bedroom, around which are articulated symmetrical secondary chambers. Originally, the dolmen was covered with a cairn or tumulus, now extinct.

Despite the degradations experienced over the centuries, the dolmen du Riholo retains remarkable elements: a terminal chamber of near square shape (2.25 m × 2 m) and an exceptionally well preserved northern lateral transept (3 m × 2 m). Two transverse pillars, placed at the cross-section of the transept, reduce access to the master bedroom, while twin slabs mark the entrance of the lateral cell. This type of architecture, dated from the Middle Armenian Neolithic (early 4th millennium BC), is shared by two other neighbouring megaliths: the double dolmen from Crévy to Saint-Lyphard and the Dolmen from Les Rochettes to Crossac.

The site was listed as a historical monument in 1980 in an already degraded state. Archaeological excavations at similar sites, such as the Cairn des Mousseaux in Pornic or the Dolmen de Château-Bû in Saint-Just, allowed these transept tombs to be attributed to a period between 4000 and 3500 BC. These collective burials bear witness to the funeral practices and architectural know-how of the neolithic communities located around the Loire estuary, an area marked by intense cultural exchanges between the two shores.

External links