The Travelcard is an inter-modal travel ticket for unlimited use on the London Underground, London Overground, Docklands Light Railway, Tramlink, London Buses and National Rail services in the Greater London area. Travelcards can be purchased for a period of time varying from one day to a year, from Transport for London, National Rail and their agents. Depending on where it is purchased, and the length of validity, a Travelcard is either printed on a paper ticket with a magnetic stripe or encoded onto a reusable contactless electronic smart card, known as an Oyster card.
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