Originally Posted by
milepig
These days with the chunnel, its very easy to add a couple days in Paris or Brussels/Amsterdam to the trip.
Would suggest this is a definite area for the OP to look into, pretty straightforward to travel on the Eurostar from within London to Paris - very reasonably priced and only takes a few hours - no visa required for entering France on a US passport, so again very convenient for a first time traveller....
For a bit of personal opinion, my GF is a USC, and bar a few days cruise in Mexico, her first long distance travel was to the UK to visit and she absolutely loved it - the sights i take for granted were absolutely fascinating to her..