London Underground with a few stations to the south of River Thames. The only London Underground stations in Zones 7 to 9 are on the Metropolitan line beyond Moor Park, outside Greater London. Some stations are in two zones, and the cheapest fare applies. Paper tickets, the contactless Oyster cards, contactless debit or credit cards and Apple Pay and Android Pay smartphones and watches can be used for travel. Single and return tickets are available in either format, but Travelcards (season tickets) for longer than a day are available only on Oyster cards. TfL introduced the Oyster card in 2003; this is
Circle line (London Underground) jointly-owned six-carriage train began passenger service in 1900. Following this an AC system was suggested, and this was accepted by both parties. However, the District was looking for a way to raise the finance needed and in 1901 found an investor, the American Charles Yerkes. He formed the Underground Electric Railways of London (UERL), and his experience in the United States led him to favour DC, with third-rail pick-up similar to that in use on the City & South London Railway and Central London Railway. After arbitration by the Board of Trade the DC system was taken up, and the