Getting around in Lyon is easy and fairly cheap compared to other European cities. Lyon takes full advantage of the Rhone Valley's roads and rivers, and transport routes into and out of the city are numerous. Air-rail links are made simple with Lyon Saint-Exupéry International Airport's TGV high-speed train station, as well as the highly developed TGV network and freeway system. The urban transport network consists of over 130 bus lines, two funiculars, four metro lines and six tramway lines. Tickets can be used across all modes of transport. A single ticket is valid for an hour and allows for multiple changes across the different forms of transport, but not a return journey. The City Card is ideal for sightseeing as you can get to most places in the city with it and receive free entry to some sites. The metro runs from 5am to midnight and night buses are available thereafter. Taxis are widely available. Commuters should make sure the meter has been reset before travelling and that the meter is on during the journey. If there is no meter then agree on a fee before setting off. Lyon's Old Town is a charming part of the city to explore on foot, and bicycles can also be rented.