Zürich S-Bahn

Zürich S-Bahn (German "S-Bahn Zürich") is a suburban rail system that links Zürich to its metropolitan area. The system started in 1990, when it was the first suburban rail system to begin operating in Switzerland.
Mid 2008, there were 380 kilometres of railway track, 171 stations and 28 lines. In 2007, about 355’653 passengers used the system every day.
Each line generally has two trains an hour. 
Since 2002, there are also 7 lines that run at night during weekends, in the nights Friday-Saturday, and Saturday-Sunday. Usually, there is one train per hour. Some lines only have one train every two hours. There are also some bus lines. Usually, traveling with these night lines requires an extra fare, which has to be bought in addition to the normal ticket.
Between 75 and 80 million people use the system every year. About 70% of the people living in the area use the system. Plans include gradually introducing 4 trains per hour on most lines, and to extend the offer to 4 trains per hour between Zürich and Winterthur during the whole day, and not just during rush hour. A new tunnel was built in Zürich main station. This tunnel allows a direct connection from Zürich main station to Oerlikon and the airport, without a change of direction.