Hatra is a ruined city that can be considered as the symbol of Parthian power which for a long time threatened that of Rome. As centre of the empire, it flourished during the 1st and 2nd centuries BC. It was a fortified city of circular design. Hatra is located in the Al-Jazirah region of present-day northern Iraq, 180 miles (290 km) northwest of Baghdad. Hatra was added to the World Heritage List as the first site in Iraq.