After all, the main Middle East character is is 'General Gamal', and the President of Egypt at the time was Gamal Abdel Nasser.
It was less than three years later that Nasser tried to blockade Israel from using the Straights of Tiran, when may have been one of the starting points of the 6-Day War.
As for Fox Studios, it is not that large. Plus there were a number of these TV series being filmed at the same time between 1965 and 1968, starting with Voyage in 1964, LIS in 1965, Green Hornet, Time Tunnel and Batman in 1966. Land of the Giants came along a little later, after some of these series had ended.
Aside from wanting to save money by reusing as much as possible. How many times did we see some variation of the Seaview diving bell on LIS and TT?
btw, something I remember from one of my visits to Fox - Christmas 2014 I received the Blu-ray set of the 1966 Batman show. We started watching the first season. At the beginning of episode
Fine Feathered Finks (1966), there was the landing of a giant umbrella, signaling the premier appearance of the Penguin.
Three weeks later, I was walking from the parking structure at the north end of the lot and came to one of the smaller surface parking lots. I suddenly recognized it as the site where the above scene had been filmed 48 years earlier. The buildings were pretty much the same, but the trees were much bigger.
Given the budgets for these shows, they reused as much as possible and I think a lot of the exterior shots, like the smaller one-story buildings surrounded by ivy or small shrubs, were some of the production offices on the west side of the lot.
It is amazing, given the low budgets, that most of these shows were able to do as much as they did. These shows, along with a few predecessors like The Twilight Zone, and The Outer Limits, and of course, the contemporary Star Trek, showed there was an audience for imaginative shows, even if the means were limited.