^^^It actually looks like a landing bay, I assumed for Taxis/transport but I can make out what looks like missiles or torpedoes, so it may be a starfleet base of some kind designed to scramble fighters in the event of an attack.
Either way, I think it's based in London.
BTW, is anyone else put off by the mile wide saucer slicing through skyscrapers at the end? THE MILE-WIDE SAUCER. >_<
Scale in Trek has always be a little fubar *cough*Voyagershuttlebay*cough* So this is just another to toss on the list. Does add to my theory that Helmsman Troi is onboard the Enterprise