Palmyra offensive (December 2016)
The Palmyra offensive in December 2016 was a military operation launched by the military of ISIL which led to the re-capture of the ancient city of Palmyra, and an unsuccessful ISIL attack on the Tiyas T-4 Airbase to the west of the city. ISIL previously controlled the city from May 2015 until March 2016.
Source: Wikipedia — Palmyra offensive (December 2016) (CC BY-SA 4.0)