Taq Kasra: The Archway of Ctesiphon
The ancient city of Ctesiphon, on the banks of Tigris, is located about 35 km southeast of modern Baghdad. Established in the late 120s BC, it was one of the great cities of late ancient Mesopotamia and the largest city in the world from 570 AD, until its fall in 637 AD, during the Muslim conquest. The only surviving structure of Ctesiphon today is the majestic vaulted hall of Taq Kasra, which served as the palace of the Sasanian king Khosrow I, in the late 6th century. The archway is one of the largest single-span vault of unreinforced brickwork in the world.
Ctesiphon was founded by Mithradates I, the king of the Parthian Empire, as a place of royal residence, after he annexed Babylonia by defeating the Greeks. Under the Parthian rule, Ctesiphon became the political and commercial center of the region, and by 58 BC, it had become the Empire’s capital. Gradually, the city was merged with the old Hellenistic capital of Seleucia and other nearby settlements to form a cosmopolitan metropolis.
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