Ketchaoua mosque is located in the lower Casbah, Algiers, Algeria. Consructed in 1612, restored and extended in 1795 under Hassan Pacha, ruler (Dey) of Algiers regency, part of the Ottoman Empire. After the French colonization in 1830 it was transformed into a cathedral. Restored as a mosque after Algeria independence in 1962. In 2015 restauration works debuted under a program of Algerian-Turkish cooperation. The restauration was achieved in 2018 and the mosque opened to the public.