On the horizon is the Citadel, the home for the rulers of Egypt for almost 700 years. The large mosque visible in the photograph is the Mosque of Muhammad Ali, built between 1830 and 1857. The flat, leaning structures on the rooftops of many of the houses are makeshift wind-tunnels, designed to capture cooling breezes and send them down into the buildings below. Acquired by the Prince of Wales, 1862