City Loop

City Loop
Overview
Type	Melbourne suburban service
System	Metro Trains Melbourne
Connecting lines	All suburban lines except Frankston, Sandringham, Weribee and Williamstown line trains (on weekdays)
Stations	5
Operation
Commenced	1971
Completed	1981
Rolling stock	Comeng, X'Trapolis, Siemens
Number of tracks	2 single bidirectional tunnels Flinders Street – Parliament 4 single bidirectional tunnels Parliament – Flagstaff 3 single bidirectional tunnels Flagstaff – Southern Cross 6 Southern Cross – Flinders Street
Route map Melbourne City Loop.png

The City Loop (originally called the Melbourne Underground Rail Loop or MURL) is a mostly-underground, partly surface-level and partly elevated subway and rail system around the central business district of Melbourne, Victoria, Australia.

The loop includes the city's two largest (both above-ground) stations: Flinders Street and Southern Cross (formerly Spencer Street); and three underground stations: Flagstaff, Melbourne Central (formerly Museum) and Parliament.

Melbourne's 15 radial suburban railway lines feed into the Loop at its northwestern and southeastern corners. The underground section of the Loop follows La Trobe and Spring Streets along the northern and eastern edges of the CBD's street grid.

Before the Loop was constructed, Flinders Street and Spencer Street (now called Southern Cross) stations were connected only by the four track Flinders Street Viaduct beside the Yarra River. The suburban terminus of Flinders Street had become seriously by the 1970s, with a throughput of only ten trains per platform per hour (roughly 1,700 trains a day) — compared to a maximum of 24 if there was through running. Many trains were through routed from the southern and eastern suburbs through to the north and west, but the flow was imbalanced and a number of trains were required to reverse direction. The Epping and Hurstbridge lines stood alone from the rest of the network, having Princes Bridge station for their own exclusive use.

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