Iwan

An iwan (Persian: ایوان, eyvān, also romanized as ivan or ivān/īvān, Arabic: إيوان, ’īwān)^[1][2][3] is a rectangular hall or space, usually vaulted, walled on three sides, with one end entirely open. The formal gateway to the iwan is called pishtaq, a Persian term for a portal projecting from the facade of a building, usually decorated with calligraphy bands, glazed tilework, and geometric designs.^[4][5] Since the definition allows for some interpretation, the overall forms and characteristics can vary greatly in terms of scale, material, or decoration.

Iwans are most commonly associated with Islamic architecture; however, the form is pre-Islamic Iranian in origin and was invented much earlier and fully developed in Mesopotamia around the third century CE, during the Parthian period.