Having gotten recommendations from this web site....we loved the London Tube. It is easy to use, well labelled. There is no guess work on which train you are going. It goes everywhere we wanted to be.We thought it was the best run subway system we have ever been on. We purchased a 7 day travel pass (zone 1 and 2) on the internet several weeks in advance for 23GBP per person....a great bargain...since single trips can be 4GBP or 8 dollars! Taxi rides were off the wall expensive....32 dollars ,without the tip from Knightsbridge to Hammersmith in the evening.