The Great Mosque of Hims, or Great Mosque of al-Nuri, is situated in the center of town, near markets and the remains of the old city wall. It is located on the site of a pagan sun temple dating to Roman times, and a later 12th-century church dedicated to St. John. It is believed that much of the modern structure can be attributed to Nur ad-Din (r. 1146-1174/540-569 AH).
Sources:
Darke, Diana. Syria, 137. Chalfont St. Peter: Bradt Travel Guides, 2010.
Reem/H.Said. "The Great Mosque of al-Nuri…a prominent aspect of Homs historical importance." Syrian Arab News Agency (SANA), August 31, 2015. Accessed November 3, 2015. http://sana.sy/en/?p=52882.