It is located on the Tigris River, 60 mi (97 km) south of Mosul, Iraq. The name Ashur was applied to the city, to Assyria itself, and to Assyria's principal god. The capital's site was originally occupied c. 2500 BC. By the late 12th century BC, Ashur was under Assyrian control. Its religious sanctity ensured its continuous upkeep until 614 BC, when it was destroyed by Babylonia. The archaeological site has yielded fortifications, temples, and palaces. It was designated a UNESCO World Heritage site in 2003.
 

source:

http://www.britannica.com/ebc/article-9355938