Severn Bridge Junction signal box in Shrewsbury, Grade II listed and the largest mechanical signal box in the world that is still operational, has just received its biggest refurbishment in more than a decade.
The 117-year-old signal box retains its original 180 levers, with 89 of them still in use today, and is responsible for signalling around 280 trains every day.
Now, thanks to a £250,000 project carried out by Network Rail and MPH Construction and partly funded by the Railway Heritage Trust, the entire three-storey building has been weather-proofed and the original single-glazed windows, installed when the building first opened in 1903, have been replaced with new double-glazed units.
In addition, the Edwardian building has received new timber cladding, repairs to its external walkway gantry and a full exterior paint job – including the famous ‘Shrewsbury’ signs that greet passengers travelling in and out the historic town by train.
Network Rail asset engineer Darren McKenna explained some of the complexities of the refurbishment: “It’s not until you can get up close to this iconic structure that you can appreciate how well built and unique it is. Working on this refurbishment was an absolute pleasure.
“The gantry repair was a big job and involved rope access teams working day and night to strengthen and replace the boards.
“We gave very careful consideration to a sympathetic repair that has managed to maintain the building’s Edwardian character while securing its future for many years to come.
“The mechanical signal box, now the world’s largest operational mechanical signal box, still plays a fundamental part on the railway by controlling safe access in and out of Shrewsbury station.”
Darren Peake is one of the signallers who operates the box: “I have been working at this signal box for around 13 years and I can tell you these improvements will make a huge difference to us, including being warmer in the winter with the new windows.
“We used to have to put pieces of paper in the gaps of the old ones. In fact, when they replaced the windows, they found newspaper cuttings behind the frames from the 1960’s.
“The history of this building is fascinating, and I am extremely proud to work from here.”
MPH Construction was the contractor that carried out the work over the course of 300 days. Construction manager Gareth Ellis commented: “We started on site in October last year and knew that this was going to be a challenging project; restoring a Grade II listed building, working at height and being completely surrounded by track.
“However, we couldn’t turn down the opportunity to work on this iconic piece of railway infrastructure and even carried out some extra works, such as renewing the eye-catching Shrewsbury sign for passengers to see.
“It has been a unique and fascinating project to work on.”