Ctesiphon

Ctesiphon, city of ancient Mesopotamia, on the eastern bank of the Tigris River, opposite Seleucia on the Tigris. Ctesiphon was the winter residence of the Parthian kings and later the capital of the kingdom of Parthia. After Seleucia was destroyed in ad 165, Ctesiphon became the leading city of Babylonia. When the Arsacid dynasty of Parthian rulers was overthrown, about ad 226, the city became the capital of the Sasanian dynasty of Persian kings. Plundered by the Arabs in 637, the city was abandoned when the Abbasid caliphs made their capital at nearby Baghdad. The ruins of Ctesiphon, in modern Iraq, are noted for the remains of a great vaulted hall of the Sasanian period.