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The Encyclopaedia Iranica Foundation was established in 1990 with the mission to guarantee the Encyclopædia Iranica's intellectual independence and ensure its ongoing publication both in digital and print versions. Learn More
The Encyclopædia Iranica is a comprehensive research tool dedicated to the study of Iranian civilization in the Middle East, the Caucasus, Central Asia, and the Indian subcontinent.
literally “four arches,” a modern term for an equilateral architectural unit consisting of four arches or short barrel vaults between four corner piers, with a dome on squinches over the central square. this unit became the most prominent element in traditional Iranian architecture after the ayvān.
The late Sasanid era. The late Sasanid winter capital was located at the urban complex on the Tigris river called “the cities” (al-Madāʾen) by the Arabs that included Ctesiphon, Aspānpur, Veh-Antioḵ-e Ḵosrow, and Veh-Ardašir.