Many archaeologists consider the twenty tombs of Sas Concas to be the most extensive and ancient Domus de Janas complex in the Barbagia region, a territory in which, unlike this site, subterranean burials are isolated or organized into small groups. The necropolis, dating back to around 2700 BC, is located in a trachyte outcrop in the territory of Oniferi, on the edge of trunk road SS 131, in the direction of Nuoro, and you can reach it via a short path. It stands out not only for its large and articulate structure, but also for its mysterious architectural and symbolic elements. In particular the walls of some of the tombs - the Hemicycle tomb, tomb X and the New West tomb - have graffiti engraved on them depicting stylized men upside down.

The Hemicycle tomb will impress you: it has a complex structure, formed by an anteroom that leads, through a door, into a large semi-circular room with a sloping ceiling. From here, you can get to another five secondary cells.