Three rail bridges were demolished in Slough and Hillingdon over Christmas in preparation for Crossrail’s new electric trains.
Network Rail has torn down the Middlegreen Road and Trenches bridges in Slough and the Old Stockley Road bridge in Hillingdon.
The new bridges will be installed at Easter.
A number of rail bridges are having to be replaced as part of the Crossrail project to provide clearance for overhead electrical equipment.
Diversions have been put in place and a temporary footbridge installed next to Middlegreen Road bridge.
The new Horton bridge, also in Hillingdon, has been installed alongside the existing one, which will be demolished at Easter.
Jorge Mendonça, Network Rail’s Crossrail programme director, said: “After months of planning, our Christmas bridge works in Slough and Hillingdon were completed on time and with as little disruption to residents as possible.
“This marks an important step for our Crossrail works, as we prepare to electrify the route, providing passengers with an improved and more reliable service.”
Matthew White, Crossrail’s surface director said: “Crossrail will transform public transport, making it quicker and easier for people to get to a range of destinations across London and the south east.
“Residents in west London and Berkshire will benefit from new trains, frequent services and better stations as part of this multi-billion pound project to improve rail services in and around the capital.”
