The line is one of three that will be completely shut down until January 19 as work on the regional rail link goes into overdrive.

Coaches will replace all trains on the metropolitan Sunbury line and on the regional Bendigo and Ballarat lines, adding an estimated 45 to 60 minutes to average journeys, while work takes place around the clock on the $4.8 billion rail project.

Buses will replace trains between Southern Cross Station and Ballarat and Bendigo, while many Sunbury line passengers will be required to hop from train to bus to train, with shuttle buses between North Melbourne and Albion stations.

Less severe disruptions will also affect Seymour and Albury services, as well as interstate services to and from Sydney and Adelaide.

The rail shutdowns coincide with major disruptions to Melbourne's freeway network from Friday night, with the staged shutdown of CityLink's Burnley and Domain tunnels, and of the West Gate Freeway.

The planned shutdown of Melbourne's busiest road, the M1, for major works is unprecedented in scale and VicRoads has warned motorists to expect delays of up to an hour, advising them to avoid the area if they can.

The M1, or West Gate and Monash freeways, which are connected by CityLink's tunnels, carries an average 180,000 vehicles each weekday. VicRoads says traffic volume falls about 30 per cent during summer holidays, which would still be more than 125,000 vehicles on those roads per day during much of the staged shutdown.

The westbound Domain Tunnel will close 10pm on Friday until 5am on Tuesday for asphalt works.

The eastbound Burnley tunnel will remain open until the new year, but close for works at 10pm on Thursday and re-open at 5am on January 7.

The West Gate Bridge will be shut down in two stages. It will be closed city-bound between Williamstown Road and Todd Road for two nights on Friday and Saturday between 11pm and 7am. Outbound, two closures will take place on January 2 and 3.

Fully signed detours will be in place.

When the Domain Tunnel is closed, traffic will be diverted via Punt Road or Batman Avenue, Alexandra Avenue and City Road. Traffic will be diverted either via Kings Way or City Road, Alexandra Avenue and Batman Avenue during the Burnley Tunnel closure.

During the West Gate Bridge closures, drivers should use Williamstown Road, Footscray Road and the Bolte Bridge, VicRoads says.

Once complete in 2015, the regional rail link will give Geelong, Ballarat and Bendigo trains their own dedicated paths into Melbourne, reducing congestion for both Metro and V/Line and creating capacity to add more services.

The Age