Shergarh

Humayun began a capital on the mound by the river in 1533 and called it Dinpanah, the refuge of faith. Seven years later he lost his empire to Sher Shah Suri, who continued building on the same ground and called the result Shergarh. Which of them the fort belongs to is still argued over, and the argument is really about who gets credit for one of the best-proportioned mosques in India, standing inside it.

Sher Shah's five years were extraordinarily productive — a rebuilt road from Bengal to the Khyber, a reformed currency, a functioning revenue system — and then he died in an explosion at a siege, and Humayun came back. He survived his restoration by six months before falling down the stairs of his own library tower in this fort. Beneath the whole site, excavation has turned up occupation going back some two and a half thousand years.