Network Rail is investing £15m to transform the Traincare Centre in Edge Hill, Liverpool.
The train depot is used by Alstom to maintain Virgin Train's fleet of Pendolino trains.
Peter Strachan, route director for Network Rail, said: "The start of the Virgin High Frequency or VHF timetable in December means that this depot will handle seven Pendolino trains each night compared with the five it currently looks after.
"In addition to this, we are also building it sufficiently long enough to take the 11-carriage Pendolino trains in the future. The investment in the depot supports the wider regeneration of the area under the Edge Lane scheme."
Edge Hill is playing a major role in Alstom`s programme to integrate the four new 11-carriage Pendolino trains, being increased from nine carriages, and additional vehicles once 31 of the trains are extended.
Virgin has stated the first of the new trains will arrive by end of 2010 and all new vehicles will be integrated and in service by 2012.