Heliopolis rewards exploration on two timescales. The ancient layer survives in a single, extraordinary monument: the Obelisk of Senusret I in Matariyya, a pink granite needle from 1950 BCE that predates most of recorded history. The modern layer is the planned suburb itself — tree-lined boulevards, Moorish arcades, and Art Nouveau villas that give the district a character unlike anywhere else in Cairo. The Baron Empain Palace, recently restored after decades of neglect, anchors the modern Heliopolis experience. For most visitors, the best thing to do is simply walk.