Mosque-Madrasa of Sultan Hassan

A Mamluk colossus so vast and costly its own architect is said to have feared it.

Begun in 1356 under Sultan Hassan, the mosque-madrasa was conceived on a scale meant to humble. Its walls rise more than 36 metres; its entrance portal swallows the street; four schools of Islamic law each got their own vaulted hall around a central court. Funded partly by the estates of those who died in the Black Death, it nearly bankrupted the treasury.

So imposing was the building that rulers later used its roof to bombard the Citadel above — and more than once ordered its stairs walled up. It remains one of the supreme achievements of Islamic architecture anywhere in the world.