Melbourne has the largest tram network in the world which had its origins in the city's 1880s land boom. In 2013–2014, 176.9 million passenger trips were made by tram. Melbourne's is Australia's only tram network to comprise more than a single line and consists of 250 km (155.3 mi) of track, 487 trams, 25 routes, and 1,763 tram stops. Around 80 per cent of Melbourne's tram network shares road space with other vehicles, while the rest of the network is separated or are light rail routes. Melbourne's trams are recognised as iconic cultural assets and a tourist attraction. Heritage trams operate on the free City Circle route, intended for visitors to Melbourne, and heritage restaurant trams travel through the city and surrounding areas during the evening. Melbourne is currently building 50 new E Class trams with some already in service in 2014. The E Class trams are about 30 metres long and are superior to the C2 class tram of similar length. Melbourne's bus network consists of almost 300 routes which mainly service the outer suburbs and fill the gaps in the network between rail and tram services. 127.6 million passenger trips were recorded on Melbourne's buses in 2013–2014, an increase of 10.2 percent on the previous year.