Airports are everywhere the same. They're like cities, with their own power grid, water, etc., their own populations, even their own police. They are cities with only a single purpose, though, so they don't look like ordinary cities. Their central place function is different. I wonder if someone will write a comparative history of airports.
Few people can really know what they're looking at just by looking. London feels historic in part because there are plaques and signs everywhere telling you that this was the only building in the district to survive the Great Fire of 1665, or that the Victoria Embankment was built in part of provide a modern sewage system to the City. I've been in numerous other old cities and they don't do this nearly so well.
The other reason why London feels historic is because we know the history. This manifests itself in two ways. First, England once ruled an empire, so many different nations and peoples have reason to know something about English history. Second, English-speaking people learned at least some English history in school; moreover, we learned English art, English literature, and so on. So in a list of fifty English names as compared to fifty German or French names, more of those English names are likely to resonant with the visitor. Learning that Mr. So-So was a noted 18th century Viennese novelist just doesn't have the same impact as learning that Jonathan Swift lived here.
This is, I suppose, one reason why travel for the historian has a different dimension than travel for one ignorant of history. We get more harmonics on our internal strings.