Nine Melbourne rail lines are going to close from April 1 to 23.
It is expected the disruption on the Cranbourne, Pakenham, Frankston, Sandringham, Glen Waverley, Mernda, Gippsland, Geelong/Warrnambool lines will affect 1.5 million passengers.
It is due to the Metro tunnel works which will happen over the period.
Buses will replace trains on all lines, with heavy delays expected.
The state government has said they are undertaking the work during school holidays so fewer commuters are affected.
The Sandringham line will re-open for Easter Monday due to an expected sell out at the MCG.