Merseytravel's all-zone, all-day tickets covering bus, train and ferry travel can be purchased at post offices. Buses are a ubiquitous form of city transport: most leave from Queen Square, east of St George's Hall, and shuttles link Albert Dock with the city centre. The famous ferry service across the Mersey was initiated by Benedictine monks some 800 years ago, making it the world's oldest ferry system. The trip from the Pier Head (north of Albert Dock) across to Wallasey takes 10 minutes and offers the best views in town. A longer look at Liverpool is afforded by the one-hour heritage cruises which run year-round. Liverpool's sole underground rail service links the city's four train stations. The city centre is pretty foot friendly, and a Mersey Cab shouldn't be too far away if you need one.