Iwan

Great Mosque of Esfahan, View of the north iwan from the courtyard

An iwan (Persian: إيوان eyvān) is defined as a vaulted hall or space, walled on three sides, with one end open. Iwans were a trademark of the Sassanid architecture of Persia. They then found their way into Islamic architecture.

Typically, iwans open on to a central courtyard, and have been used in both public and residential architecture.