sole purpose of getting to downtown Helsinki. These lines tend to use the fastest possible way to get out of Helsinki, usually through motorways. Lines from southern Espoo terminate at Kampin keskus during peak hours only, the ones from central Espoo and western Vantaa terminate at Elielinaukio and the ones from northern Vantaa and Kerava terminate at Rautatientori. The last two mentioned are located next to the central railway station. Some lines from central Espoo terminate at Kamppi instead of Elielinaukio. The operating hours for regional lines are similar to those of internal lines, but the departures are often not as frequent. At most times, the line numbers are composed of three digits and occasionally a letter or two accompanying them. Two-number regional lines are rare, and thus far only two have been created: 39 Kamppi-Myyrmäki (replaced by trunk bus 30) and 74 Hakaniemi-Porttipuisto (IKEA). Tram Helsinki's tram network has been operated continuously with electric drive since 1900 and it is mostly of a traditional type, with all of the tramways located on the streets, on both dedicated tram lanes and in mixed traffic. The network covers the densely populated central districts and some of the adjacent areas, but it has been expanded only very modestly after the 1950s. The network is composed of 10 lines, all of which except one (line 8) run through some part of the city centre. Over 50 million trips are made with the trams each year. The tram system is managed and operated by HKL. Metro The metro is the backbone for traffic east and west of central Helsinki. The system consists of two lines, M1 and M2, with a total of 25 stations. The metro is managed and operated by HKL. Commuter rail The commuter rail system is the backbone for the areas northeast and northwest from downtown. The network reaches relatively far from Helsinki with metro-like services from Helsinki to Kerava, Kirkkonummi and the Helsinki Airport. The network is managed by HSL and operated by VR. Trains not managed by HSL reach even further, to Lahti, Tampere via Riihimäki and Kouvola. Ferry Helsinki has two ferry lines, both operated by Suomenlinnan Liikenne Oy. One ferry connects Suomenlinna to the mainland. The ferries are the only connection to the mainland for the residents of Suomenlinna, though a tunnel for emergency vehicle access is in place. The second line connects the mainland to the