The mosque erected by Muhammad ‛Ali (reigned 1805-1848) is the most prominent monument in Cairo . Its commanding location on the Citadel enables its soaring twin minarets to be seen throughout the city, and the combination of dome and semi-domes is successful as silhouette. Work started in late 1828 under Yusuf Bushnaq, a Greek from Istanbul, and continued for at least nine years after Muhammad ‛Ali's death. The exterior was covered (the first 11 meters) with alabaster, which has weathered badly. The complex includes a mausoleum.