Baghdad
A round city built from nothing becomes the largest in the world.
- When
- Known to
- ± 1 year
- Era
- Post-Classical, Holocene
Al-Mansur founds Baghdad in 762 as the Abbasid capital, laid out as a perfect circle with the palace and mosque at the centre. Sited where the Tigris and Euphrates run close together and on the routes to Persia, India and Central Asia, it grows within a century into the world's largest city, plausibly the first to reach a million people, and the intellectual centre of the Islamic world.