A new rail bridge is up and running in central Hammersmith after being installed in one weekend.
Workers from London Underground achieved the engineering feat after an 80-year-old bridge carrying District Line trains over Cambridge Grove was found to have a serious problem with rain water collecting and causing it to rust.
Replacing the entire structure was seen as more economical than attempting to repair it, so a new 85 tonne bridge was built off-site in Newport, Wales, at the same factory which built the contoured roof of the Olympic Aquatic Centre.
The length of Cambridge Grove, which dips as it runs beneath the Tube line, had to be levelled off with 280 tonnes of stone so specialist vehicles could manoeuvre the new bridge into place.
Foundations 21 metres deep were piled into the ground to support the steel and concrete structure, which is insulated with an acoustic mat to reduce the rumble of overhead trains.
Once the bridge was in place, an engineering train was brought in to help lay new track, sleepers and ballast.
The road was closed to traffic for several weeks in advance of the project. Contractors from Vinci Construction began lifting the structure into place at 3am on Saturday, November 6, and had finished the work in time for District Line trains to start running again on the morning of Monday, November 8.
London Underground's project manager, Kirit Patel, said: "The layout of the road and close proximity of residents in the area made it a huge challenge. Due to the heavy nature of the equipment needed for the job, the road needed to be levelled. Machines had to be brought in from Holland by our contractor."
The new bridge, between Hammersmith and Ravenscourt Park Tube stations, is designed to last 120 years. Lighting beneath it will now be improved, footpaths will be widened, some fencing will be removed and the area will be cleaned.