Bicing is Barcelona's version of the public transport concept available in many European cities. By paying an annual fee of €47.16 (though the city government is considering a significant increase) members of Bicing get a card they can use to take a bicycle from one of the terminals placed all over the city. The first 30 minutes are included in the fee, but if you exceed that time limit, you'll have to pay 74 cents for every extra half hour. The bikes cannot be used for more than two hours in one journey, and once you've arrived at your destination, you must leave it at the nearest terminal.
If you're a city resident, you can sign up at the Bicing website (www.bicing.cat) or in person at their offices in Plaça de Carles de Pi i Sunyer, 8. Bicing operates 365 days a year, 24 hours a day (except Mon-Fri, when the stations are out of service between 2am and 5am).