The centrepiece of modern Heliopolis and one of Cairo's most startling buildings. Édouard Empain, the Belgian industrialist who built the entire suburb from scratch beginning in 1905, commissioned this mansion for himself in 1911. The architect Marcel Lauwerys drew on Cambodian and Hindu temple architecture — Angkor Wat is the obvious reference, but there are Indian elements too — and the result is a fantasy: a layered stone tower with carved reliefs, serpentine balustrades, and a revolving upper room that Empain reportedly used to follow the sun. For decades after the Empain family's departure it stood empty and deteriorating, a ruin that became the focus of ghost stories and urban legends. After a lengthy restoration programme it is now open to the public, and the interior — with its grand staircase, tiled floors, and exhibition on the palace's history — does justice to the extraordinary exterior. One of the genuinely unmissable buildings in Egypt.