Sydney underground railways

Sydney, the largest city in Australia, has an extensive network of passenger and freight railways. The passenger system consists of an extensive suburban railway network, Sydney Trains, which has a central underground core running at metro-equivalent frequencies, and a light rail line, running on a formerly disused line that was a part of the separate network of freight lines. Sydney Metro is a rapid transit system under construction, that will be operated independently from the current train network, but interchange with it.

The existing network has some things in common with conventional rapid transit systems, including 20 hours a day operation, 15 minute or better frequencies on most of the network, large underground sections, a ridership comparable and even larger than most North American rapid transit systems and relatively small distances between stations.

Passenger service in Sydney is operated since 2013 by Sydney Trains. Trains operate for 20 hours a day, and over 1 million weekday passenger journeys are made on 2365 daily services over 2080 km of track and through 306 stations (including interurban lines). Suburban services operates along the portions of the main lines from Sydney to the north, west, south and south-west, and also along several dedicated suburban lines. All of these lines are electrified at overhead 1500 V DC, starting in 1926. Some of the suburban stations are also served by the intercity and regional trains operated by NSW TrainLink.

Most suburban services operate through central Sydney via the underground City Circle (not a true circle line but a two-way loop extending under the CBD from [{Central Station]]), the Eastern Suburbs underground line, or over the Harbour Bridge. There are have been long term plans for a new underground line passing beneath Pitt Street to a new harbour crossing. Currently this ling is in the advanced planning stages as a rapid transit line, with construction expected from 2017-2024.

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