The most recent underground section of rail infrastructure that was built in Sydney is the Epping to Chatswood Rail Link, opened in 2009. This consists of 13km twin tunnels running with Stations at North Ryde, Macquarie Park and Macquarie University. The original plan was for a Chatswood to Parramatta link, however the NSW Government ran out of money to complete the project.
Finally, the North West Rail link, currently under construction, will eventually link up with the Epping to Chatswood rail link, creating the first major section of the Sydney Rapid Transit System. The Sydney Rapid Transit System will eventually link the North west, North Shore, CBD, Inner West and Bankstown Areas with Single deck metro style trains.
~ Cameron
Sydney has a rather extensive railway network above ground, however, some of the network is located in subterranean Sydney. Small tunnels are common across the network, however, extensive tunnel portals started to become common especially in built up areas since the 1950's, during the construction of the City Circle Line.
In the 1960's, after the demise of the Sydney Tram Network, the largest Tram network in the Southern Hemisphere at its peak, the government decided it needed a replacement in the Eastern Suburbs as Buses were not adequate for Sydney's growing population. To solve their solution the Eastern Suburbs Line was built in the 1970's from Redfern to Bondi Junction. In the 1990's, it was decided the Airport needed a rail link, so the Government built an underground train line between Central and Wolli Creek via Green Square, Mascot & Both Airport Terminals in a Public-Private ownership with Macquarie Bank, resulting in an additional Station Access Fee to use the Airport Stations.
~ Cameron
