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London's mayor, Boris Johnson, is a real cycling enthusiast and keen to make the capital more bike-friendly. A 24-hour bike-rental program, currently called Barclays Cycle Hire but with a new sponsor set to be announced in 2015, enables Londoners to pick up a "Boris bike" at one of more than 700 docking stations and return it at another. The first 30 minutes are free. After that, charges rise incrementally from £1 for one hour up to £50 for the entire 24 hours. There is also a £2-per-day access charge. Fees are payable online, by phone, or at docking stations, by credit or debit cards only—cash is not accepted. To sign up, a user goes to the TfL (Transport for London) website and then receives a bike key in the mail, so this very popular system is really only practical for locals, not most tourists.