I've read this site's top questions and other sites as well before posting this but I'm not sure how to manage transportation. We will be in London for 3 days, and 3 nights, in zones 1-2. We are two adults and 2 kids, ages 11 and 14. We will be going to the Tower of London & London Eye, which I know have the 2-4-1 deal with them. The first day we will land at Gatwick in the morning, take a taxi to our hotel, and then take the transport to the Tower of London and most likely the Westminster area. The second day, after we get to central london by transport, we will be mostly walking except for one transport and another to get back to the hotel at night. The last day, we will be using transport probably a lot. Should we get a 3 travelcards for the 3 days or just an oyster card? Thanks!