Which country has the most universities in the top 5 in the world? Well, the US isn't it, surely, given the size of the country and the amount of money their universities have in endowments.
Apparently, no. It's the UK, thanks to Cambridge, Oxford and Imperial College London. If you believe the Times Higher Education Supplement, anyway (or at least, the BBC News story about it, as I can't find the actual list on the THES website, so no idea where my employers are yet).
The US still has the top establishment (Harvard) and 6 of the top ten to the UK's four.