Azraq is located on a key caravan junction with converging
roads from Saudi Arabia, Jordan, Iraq and Syria, with large pools
of fresh water.
While the large fort is most likely Roman, based on Latin
and Greek inscriptions from the 3rd and 4th centuries referencing
Diocletian, the mosque dates back to the Umayyads. You can see
the lighter colored mosque in the dark area of the fort above.
The Umayyads did not seem to refortify the Roman fortifications.
It is reasonable to suppose that Umayyads saw Wadi Sirhan (and
the oases at Jauf and Azraq) rather as the central corridor of
the Islamic world and the conduit between Arabia, Iraq and Syria.
The cities of Madinah, Kufah and Damascus. Rather the Umayyads
used Azraq for recreation, rest and relaxation, and they patrolled
the traffic that went beyond Azraq. All the water points on routes
leading out of Azraq were patrolled by an Umayyad Qa?r. This
Umayyad mosque points to within 2.62° of a between qibla.