... https://www.youtube.com/watch?v=yG4xBcJvjCk

"To make a long story short, the closed-off Soviet Union (it's behavior and attitude with the West characterized by the term 'iron curtain') denied overflight rights to many international airlines. One of the most significant outcomes of this policy was that travel between Europe and Asia could not access the 'Siberian corridor' - flying over the Soviet Union (Russia today). In the absence of geopolitical factors, this would be the most efficient way to fly between the two regions of the world. With the range of many aircraft at the time, a refueling stop would have been required somewhere in the Soviet Union - but it would still have been more efficient than going through Anchorage. Flying around the 'Iron Curtain' With the USSR's airspace closed to many airlines, a workaround had to be developed to connect Europe and Asia. The solution: Anchorage Airport in Alaska. The 2nd most efficient way to fly between Europe and Asia was to fly a polar route north of Soviet airspace. For all passenger aircraft at the time, going north and around this airspace meant that a fuel stop was necessary to go the distance." https://simpleflying.com/asia-europe-alaska-stopover/ ... https://www.youtube.com/watch?v=nQ3iABmHYcY