Area around the Great Pyramid, likely taken during Mazer's journey to the CBI. During WWII.
It is quite possible that Mazer deployed overseas as a replacement aboard ATC transport aircraft, not knowing to what unit/plane he would be assigned until his arrival in India or China. If so, this eclectic group might even be a sampling of the people on a recent group flight.
(Thanks to Tony Strotman for additional information.)