The centro storico (historic center) of Florence is small and very walkable, especially since large areas have been pedestrianized. The efficient bus network, run by ATAF, includes a fleet of Lilliputian electric buses (routes A, B, C, and D) designed to navigate the narrow streets of the city center. Single tickets for all routes cost €1.20 and are valid for 90 minutes. 24-hour passes cost €5. Taxis are available on designated stands.