Hi their website says three, with additional three walking tours and a riverboat cruise. We had a two au ticket, which was great value, and a free river cruise. However, time goes quickly so do not be too ambitious in how many stops you will actually make, and plan carefully. The ‘live’ commentaries were really good, and the recorded ones were fine. Under fives go free, which was a real bonus for us as we had two young grandchildren. The river cruise was great, giving a different view to London. Well worth doing. Do not expect ANY of these companies to run to a tight schedule as traffic/lights/ time of day make a big impact on a schedule.