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London's first and only cable car, known as the Emirates Air Line, opened in June 2012. Crossing the River Thames, linking Greenwich Peninsula and the Royal Docks in the east of the city, the cable car is integrated with London's Oyster Card ticketing system, although special fares are charged. Costing £60 million to build, it carries over 3,500 passengers every day, although this is very much lower than its capacity. Similar to the Santander Cycles bike hire scheme, the cable car is sponsored in a 10-year deal by the airline Emirates.

Roughly how many passengers travel daily on London's cable car?
3,500