The oldest standing obelisk in Egypt, and one of the oldest in the world. Senusret I raised it around 1950 BCE at Iunu — the ancient City of the Sun, the great centre of Ra worship that would eventually give Heliopolis its Greek name. Almost everything else from ancient Iunu has long since been quarried, buried, or carted off to Rome; this single pink granite shaft, 68 tonnes of it, has stood in place for nearly four thousand years. It now stands in the working-class neighbourhood of Matariyya, a short taxi ride north of the main Heliopolis boulevard, surrounded by an open-air site that also contains fragments of other ancient stonework. The scale is hard to grasp until you are standing beneath it. A genuinely extraordinary survival.