The older and more rugged of Matera's two cave districts, carved into the southern ravine. The Sasso Caveoso is less restored than its northern counterpart — more crumbling walls, more empty caves, more of the raw atmosphere that made the Sassi famous as a symbol of southern poverty before they became a symbol of UNESCO heritage. The lower sections, where the ravine deepens, retain structures that were still being inhabited in the 1950s. The church of Santa Maria de Idris is carved directly into the rock face here, its exterior barely distinguishable from the cliff.