Ctesiphon

The ruins of the ancient Persian capital, Ctesiphon, are located 35 kilometers/22 miles southeast of Baghdad, the capital of Iraq, and are one of the ancient world's great unknown wonders.

Ctesiphon was a minor Persian village on the banks of the Tigris River around the middle of the fourth century BC. However, in the first century AD, it became the Parthian capital and expanded to incorporate the city of Seleucia. This meant that by the 7th century, Ctesiphon had grown to become one of the largest towns in the region, and it was here that the Arch of Ctesiphon was built.

Taq Kasra, the world's most colossal single-span vault of unreinforced brickwork, is now the only remaining structure on Ctesiphon and is regarded as a monument in the history of architecture. Taq Kasra was part of a magnificent vaulted hall that served as the palace for the Persian Empire's monarchs, but after the Arabs invaded Ctesiphon, the palace was utilized as a Mosque for a short time until the entire city was abandoned.

Location: Salman Pak, Baghdad Governorate, Iraq