We just finished a 3 week trip that included London, Paris, Rome, Florence, Verona and Amsterdam. Some thoughts on transport: If you land at Heathrow (LHR), don't waste money on the Heathrow Express - for $7 you can catch the tube to London (usually Hammersmith station) and change into all the city tube lines to your hotel or whatever. If you buy Zone1/2 tube passes before you leave, they won't cover the trip from LHR. You buy a separate ticket at the airport. But that ticket will allow you to continue your subway trip all the way to your hotel, so you won't begin using your pass until you set out to sightsee. Buy the pass (1, 3, 7 day versions) - it will probably save you lots of money over the single fare rate.