Metro Tunnel
The Metro Tunnel (sometimes also known as the Melbourne Metro Rail Project or the Metro Rail Capacity Project) is a metropolitan rail infrastructure project currently under construction in Melbourne, Australia. It includes the construction of twin 9-kilometre rail tunnels between South Kensington station (north west of the Melbourne City Centre) and South Yarra (in the south east) with five new underground stations. The southern portal for the tunnel is to be located to the south of South Yarra station. As a result, the tunnel will connect the Pakenham and Cranbourne lines with the Sunbury line, and allow these lines to bypass Flinders Street station and the City Loop while still stopping in the Melbourne central business district.
Railway tunnels in Victoria, Australia
The Melbourne–Echuca railway or Bendigo line was commenced by the private Melbourne, Mount Alexander and Murray River Railway Company, but when the company experienced financial difficulties it was taken over by the Victorian colonial government in 1856, with the Victorian Railways Department being formed to operate the new public railway system. The line opened in five stages from February 1859 to September 1864, and was at the time the largest engineering undertaking in the colony. More than 6,000 men were involved in construction of the Bendigo line with the main contractors Cornish and Bruce undertaking the works. The line served a strategic economic need of serving the important goldfields of Castlemaine and Bendigo (then called Sandhurst), and capturing for Melbourne the trade in wool and other goods from northern Victoria and the Riverina which were formerly shipped through South Australia via the Murray River. Two tunnels were built on the line. The Elphinstone Tunnel, long, was built in brick and bluestone as a double-track horseshoe profile tunnel, and was completed in 1860. The Big Hill Tunnel, located between Kangaroo Flat and Ravenswood, south of Bendigo. Like the Elpinstone Tunnel, it was double-tracked when built, but was singled as part of the Regional Fast Rail project. 
Cheviot tunnel was built for the extension of the Mansfield railway line from Yea and is located near Limestone, roughly halfway between Yea and Molesworth, where the line crosses the Black Range at McLoughlin's Gap. It was built in 1889, at a cost of £88,661/2/11, by contractors by Kenny Bros. as part of the Yea to Cathkin section, but construction was delayed by accidents.