The Sidi Salim mosque adjoins the royal tombs at the edge of the old ksar and is the principal historical mosque of Touggourt. It was built by Sultan Salim of the Beni Djellab dynasty in the seventeenth century, in the traditional Saharan style — sand-coloured mudbrick walls, a single squat minaret, and a flat roof scattered with small domes.
Non-Muslims are not normally admitted to the prayer hall but can view the exterior. The setting, next to the kings' tombs and on the edge of the old town, is among the most evocative in Saharan Algeria.