My family of 4 adults will be visiting London for 11 days in early Sept. We have rented an apt. about 3 blocks south of Westminster Abbey. Since this is our first visit to London we plan to see the major tourist places. I am having trouble understanding the 2 for 1 Offer. Are we too close to the attractions such as Tower of London, Kennsington Palace, Hampton Palace to buy/use a Travel Card for the 2 for 1 Offer? What is more cost effective or practical-to walk to the tourist places that are near by, buy Oyster cards or get Travel Cards and use the 2 for 1 Offer?
Even if you walk a lot--and London is a great walking city--there still will be times you'll want to take either the Tube or the bus. And if you go to Greenwich, you'll probably ride the Docklands Light Railway.
I assume you've looked at the list of 2for1 offers found here that are covered by a National Rail PAPER travelcard sold only at mainline train stations, not Tube stations. I suggest that you buy one-day National Rail paper travelcards for each day you plan to take advantage of any 2for1 offers. Buy Oyster cards when you arrive, load about £20 on each of them, and use them as pay-as-you-go cards on days you don't use a National Rail travelcard. The Oyster computer will calculate the best fare for you and on any given day you will pay no more than 50 pence less than the cost of a one-day travelcard for the zones in which you travel that day. You'll use very little of the balance on your Oyster cards on days you walk a lot or ride the bus rather than the Tube. Top off the Oyster cards as needed and get a refund of any unspent money (including your deposit) when you leave. Or save the Oyster cards for your next trip to London!