Until recently, Hatra was the best-preserved ancient Parthian city. The fortress was built between the 3rd-2nd century BCE, protected by nearly four miles of inner and outer walls. Hatra was the capital of the first Arab Kingdom, and was referred to as Beit ʾelāhāʾ (House of God) due to temples celebrating Greek, Aramean, Mesopotamian, and Arabian gods.
The Sāsānian king Ardashīr I ‘destroyed’ the city in the 3rd century, and the impressive ruins went undiscovered until the 19th century. In 2015, UNESCO added Hatra to its endangered list after Isis militants fired bullets into walls and towers and used sledgehammers to destroy statues they considered “signs of polytheism.”