Alstom Completes Major Cambridge Signalling Milestone Over Christmas

Alstom has marked a major milestone on one of the UK’s largest signalling schemes after successfully completing Stage 2 of the Cambridge Resignalling, Relock and Recontrol programme, a project designed to modernise rail infrastructure and improve performance across the region.

The latest phase of the C3R project was delivered for Network Rail over the Christmas and New Year period, with teams working continuously to complete a complex commissioning programme on schedule. The work covered the area north of Cambridge station, through the new Cambridge South station site, and southwards to the boundaries at Great Chesterford and Foxton.

As part of the upgrade, the long-serving NX panel at Cambridge powered signal box was removed and replaced with two new Modular Control Systems, introducing modern control technology to the route. Safety was also enhanced at Meldreth Road level crossing, which has been upgraded from an automatic half-barrier layout to a fully controlled MCB-CCTV system.

To allow the work to be carried out safely, Cambridge station and surrounding routes were closed for 11 days from Christmas Day 2025 until the morning of Monday 5 January 2026. Around 250 people worked on each shift across 23 shifts, contributing more than 50,000 hours. Alstom said the operation represented its largest-ever single re-signalling project in the UK.

Stage 2 forms part of Network Rail’s wider £200 million investment to renew signalling equipment across the Cambridge area, much of which had been in service for more than four decades. The upgrade also prepares the route for future digital technologies, including the European Train Control System.

The new arrangement uses Alstom’s Smartlock 400 interlocking and MCS Infinity control platform, offering greater reliability and operational flexibility while supporting future developments such as the opening of Cambridge South station later this year. In total, the works involved more than 100 signals, 76 point machines, over 300 axle counter sections and 323 signalled routes controlled by two new interlockings, alongside nine level crossing recontrols and the transfer of control for the SSI and RRI interlockings south of Whittlesford.

Shortly after midnight on Christmas Day, the original signalling panel at Cambridge PSB was taken out of service for the final time after more than 40 years. Before shutdown, a simple “FAREWELL” message appeared on the panel as the mechanical relay room was powered down.

Alstom secured the £130 million design and delivery contract for the Cambridge re-signalling project in 2022, the largest single award made by Network Rail under its Major Signalling Framework Agreement. Work will now continue into Stage 3 during 2026, covering most remaining level crossing upgrades and the recontrol of the Ely to Norwich route. Stage 4 is planned to bring the Newmarket and Bury St Edmunds resignalling into use during 2027.

Emmanuel Henry, Digital and Integrated Systems Managing Director UK and Ireland at Alstom said:

“This successful commissioning demonstrates Alstom’s commitment to delivering cutting-edge signalling solutions that enhance safety and efficiency across the UK rail network. We are proud to play a key role in transforming the Cambridge area for the benefit of passengers and operators alike. The achievement reflects the dedication and professionalism of everyone involved – from installation and testing crews to engineering, planning, safety, logistics and project leadership. Alstom extends its gratitude to Network Rail and our supply chain for their trust and support throughout this project.”

Darren Hay, Senior Portfolio Manager for C3R at Network Rail said:

“Re-signalling projects of this size and complexity are not easy to deliver, but the determination and professionalism shown by the project and operations teams, and in collaboration with the train operating companies, has been exemplary. The successful completion of Stage 2 is a testament to how well everyone worked together to plan and deliver this commissioning stage for Cambridgeshire with the accuracy and control required to be able to hand the railway back to passengers on time. A huge thank you and well done to colleagues at Network Rail, Alstom, their supply chains and the operations staff.”

Image: Alstom