To use the free city bikes in Paris (there's lots of them at Gare du Nord and outside all metro stations) you just need your credit card for a 150 Euro deposit.
They give you a 24hour pass for just 1 Euro and you get to use the bikes as often as you like, keep it to 1/2 hour slots and you don't pay a penny more.
Send your feedback or queries to been.there@guardian.co.uk
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