Bologna's city centre is compact, and the narrow cobblestone streets are great fun to wander through, so walking is a great way to see the sights. Bicycles and motorbikes are also a common sight. Visitors worried about getting lost in the labyrinthine passageways can take advantage of the excellent bus system, which runs from 6.30am until late. A City Pass is a cost-effective way of taking multiple journeys. Taxis and rental cars are also available but much of the city centre is off-limits to cars, negating much of the convenience.