The manufacturer Stadler Rail recently secured two major orders: one for Aarhus Letbane in Denmark and the other for the planned Regionaltangente West (RTW) in the Rhine-Main area for Rhein-Main-Verkehrsverbund (RMV). Both procurements rely on the flexible CITYLINK tram-train system — a strong signal for the growing importance of tram and regional light rail concepts in Europe.
Both vehicles are based on the CITYLINK family, which was manufactured for the Spanish market back in 2003 by Stadler Valencia’s predecessor company, Vossloh. The largest CITYLINK order to date was awarded at the beginning of 2022 for the VDV dual-system light rail system. We reported on this here.
Aarhus expands fleet – winter-proof and battery-powered
On 2 December 2025, Aarhus Letbane ordered eight new battery-powered CITYLINK vehicles; an option for twelve additional units was also agreed. The four-car tram-trains are designed for the Danish winter: with on-board batteries, they can run even when the overhead lines are icy — a decisive advantage for reliable operation in all seasons.
Stadler is building the vehicles at its plant in Valencia. The CITYLINK trains can carry up to 324 passengers (152 seats, 16 of which are flexible), are barrier-free and meet comfort and environmental requirements thanks to their hybrid drive and high passenger comfort. With this order, Aarhus is responding to growing demand and strengthening the light rail connection between the city and its surrounding area — with an option for further expansion. To date, 12 Stadler Tango and 14 Variobahn trains are in operation on the Letbane.
Frankfurt: CITYLINK for Regional Tangent West (RTW)
At the same time, Stadler secured the contract to supply 27 CITYLINK vehicles for the new RTW line. In addition to delivery, the contract also includes long-term maintenance over 30 years. The approximately 50-metre-long vehicles are also dual-system vehicles, meaning they can operate on both conventional railway lines and light rail lines. With a capacity of around 360 passengers and barrier-free access at different platform heights, they enable flexible, continuous operation without the need to change trains.
The first units are scheduled to be delivered for testing in autumn 2028, with the entire fleet to be delivered by autumn 2030 — in time for the planned launch of regular RTW services when the timetable changes in December 2030.
Stadler Rail AG has been awarded the contract in the Europe-wide tendering process conducted by Fahrzeugmanagement Region Frankfurt RheinMain (fahma), the vehicle management subsidiary of Rhein-Main Verkehrsverbund (RMV), for the new dual-system vehicles for Regionaltangente West (RTW).
The vehicles are being redesigned to meet the specific requirements of RTW. As dual-current system vehicles, they can run on both mainline and light rail routes. The approximately 50-metre-long vehicles will have a capacity of around 360 passengers and enable barrier-free travel at different platform heights. The variety of platform heights used by Deutsche Bahn (76 and 96 cm) and the use of RTW’s own platform height (80 cm) mean that RTW vehicles must be able to serve multiple platform heights.
Delivery of the first three vehicles for testing and approval purposes is scheduled for autumn 2028. The entire fleet is expected to be available by autumn 2030. Full operation of the RTW is still planned for the timetable change in December 2030. In addition to delivery, the agreement also covers maintenance, servicing and spare parts supply for the vehicles over a contract period of 30 years.
The Regional Tangent West
Die Regionaltangente West (RTW) soll das Verkehrsnetz im Rhein-Main-Gebiet grundlegend verändern: Statt wie bisher sternförmig ins Zentrum Frankfurt zu führen, wird eine tangentiale Schienenverbindung geschaffen, die periphere Städte und Gemeinden direkt miteinander verbindet. Damit entlastet die RTW den überlasteten Frankfurter Hauptbahnhof sowie das S-Bahn-Stammnetz und bietet Pendler:innen direkte, umsteigefreie Verbindungen — zum Beispiel zwischen größeren Vororten, dem Flughafen, wichtigen Arbeitsplätzen und Wohngebieten.
Network and routes
The RTW covers a total distance of around 52 km, of which approximately 22–23 km will be newly built. Two lines are planned, which will run together in the core area between Eschborn and Neu-Isenburg, where a 15-minute interval is to be possible, while each line will run every 30 minutes on the outer branches. A total of 28 stops are planned, including 12 existing S-Bahn stations.
Vehicles and operation
The RTW relies on dual-system vehicles (‘tram-trains’) that can operate on both railway and light rail/tram-like sections, allowing regional and urban areas to be connected without the need to change trains. The barrier-free infrastructure must compensate for different platform heights of 76 cm (regional transport), 96 cm (suburban railway) and around 80 cm on its own platforms. Although the RTW will operate as a tram/light rail system away from the main railway lines, there are no plans to interoperate the tram-trains with the Frankfurt light rail system.
Even with just two lines, around 2.6 million additional train kilometres would be covered each year. A quarter-hourly service is planned between Eschborn and Neu-Isenburg — a significant increase in frequency compared to many of today’s regional connections. The daily passenger volume is forecast to be between 30,000 and 50,000, which could encourage many commuters to switch from car to rail.
Planning stages and start of construction
Three of the five planning approval sections (PfA North, South 1, Centre) have now been granted building permits: North in June 2023, South 1 in January 2022, Centre in August 2024. These sections are currently under construction. Official construction began in 2017, with initial construction work starting in 2022/2023. Partial commissioning of the southern section (e.g. Kelsterbach – Airport – Neu-Isenburg) could take place as early as 2026; the original target for full commissioning was 2028, but delays are currently expected — completion by 2029 is now considered more realistic.
Financing
The RTW is a key infrastructure project in the Rhine-Main region, supported by the state, local authorities and the RMV. It is intended not only to improve mobility, but also to better connect economic locations (airport, Höchst Industrial Park, commercial areas in the west) and promote sustainable development in the region. The increase in the necessary funding was again approved in 2025 — a sign of the political will to push ahead with the project despite increased construction costs.
05.12.2025
