According to the Wikipedia article and the original source Gander International Airport
had four runways and was the largest airport in the world
Now, "large" can mean a lot of things, as in
- the number of runways
- the surface area covered
- the total area or volume of buildings
- the number of airplane operations or passengers (you would typically use "busy" then, but who knows)
but I'm not familiar enough with airport history to know which ones I would have to compare it to. LaGuardia for example was opened on Dec 2, 1939 and also had four runways.
So, my question is, by what measure was Gander the largest airport at the time (of course, assuming, that it actually was, by any reasonable measure)?