Assur, also known as Ashur, Qal'at Sherqat, Kalah Shergat, was a city in the Neo-Assyrian Empire. The remains of the city are situated on the western bank of the river Tigris, north of the confluence with the tributary Little Zab river, in modern-day Iraq. The city was occupied from the mid-3rd millennium BC (2600-2500 BC) to the 14th century AD. The Site was inscribed as a UNESCO World Heritage Site in 2003.