I am only a couple of blocks away from a McDonalds, just in case!
That doesn't awlways work well. When I visited Singapore, I had McDonald's...and the only familiar menu item I can recall was chicken nuggets.I can't suggest anything to do during your long layover aside from meeting up with the UK contingent if won't be at night.Have yourself a great trip!
Killing time at London Heathrow Airport you say?Not easy... I would ask Surge if I were you