Visiting Cairo's Mohamed Ali Mosque invites an exploration of the grand, domed interior's multiple sources of light. None are greatly illuminating. This image shows the many lighted lanterns hanging from a gigantic chandelier suspended below the spacious dome overhead. But the brightest light comes from the mosque's few entryways, used by tourists and a few of the faithful, for it no longer serves a religious function. The mosque was built in the early 1800s on the ruins of Suleiman's 11th-century Citadel.