Take the Tube Challenge 07 on 18 May
Most days, using London's Tube system is an ordeal. But during Tube Challenge 07 it is turned into a race course for especially intrepid types.
On 18 May, teams will square up and frantically visit every Tube station within Zone 1 (Central London) in as little time as possible. The current record to visit these 63 stations is a little under 3 hours.
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