Denmark’s ERTMS rollout: The world’s largest digital rail signalling upgrade

Denmark’s Signalling Programme is not only ambitious in scale, it is a first-of-its-kind full-network upgrade, replacing all legacy rail signalling infrastructure with ETCS Level 2 and CBTC (Communications-Based Train Control) technology across more than 2,600km of track.

This €2.7 billion investment is transforming the country’s railway into a digitally integrated, interoperable, high-capacity, and resilient transport network, positioning it as a live case study for other countries that plan to implement ERTMS.

Prior to the programme’s launch, Denmark faced serious limitations with its ageing analogue signalling systems — over half of which were more than 50 years old. Frequent signal failures caused significant operational disruptions and delays.

Rather than apply incremental fixes, Danish national rail operator, Banedanmark, chose a comprehensive system renewal. On the mainline network (Fjernbane), ETCS Level 2 Baseline 3 is being rolled out nationwide with a view to reducing signal related delays by 80%.

Meanwhile, Copenhagen’s S-Bane — serving the city’s dense urban network — has transitioned to CBTC GOA2 with Automatic Train Operation (ATO). Since the completion of the work in 2022, 96.4% of trains arrived on time in the year from September 2022 to September 2023.

This integrated approach not only modernises the rail infrastructure but also aligns Denmark with European rail interoperability standards.

The Danish Signalling Programme goes far beyond traditional signalling upgrades. It includes a nationwide GSM-R network, a fibre-optic transmission backbone, and two new traffic control centres that manage train operations using real-time data.

A new Traffic Management System (TMS) monitors train movements, handles disruptions dynamically, and provides accurate passenger information systems across the network. These features ensure increased service reliability, enhanced rail traffic efficiency, and an improved passenger experience.

For ERTMS suppliers and rail technology companies, Denmark’s model showcases what a large-scale integration of signalling, telecoms, and digital rail control systems can achieve.

To manage the complexity of the programme, Banedanmark appointed a consortium led by Ramboll, alongside Atkins (now SYSTRA), Emch+Berger, and Parsons — the largest consultancy contract ever awarded in Danish rail history.

Since 2007, the consortium has been part of all phases of delivery from strategic analysis, programme planning, procurement, and implementation including:

• ERTMS and CBTC procurement strategies and tender evaluations
• Programme and project management
• Systems integration, interface testing, and joint ERTMS test labs
• Reliability, Availability, Maintainability & Safety (RAMS) compliance, operational change management, and staff training
• Organisational design, business benefit realisation, and migration planning

By aligning supplier coordination with clear performance goals and life-cycle cost strategies, the programme demonstrates how to manage a nationwide railway signalling migration at scale.

Denmark’s Signalling Programme is already serving as a reference for other ERTMS projects across Europe and highlights best practices in:

• Brownfield infrastructure integration
• Design-Build-Maintain (DBM) contract strategies
• Full network signalling migration and testing
• Supplier engagement for system-wide interoperability