With the introduction of the new S-Bahn line S15 on 15 June 2026, Berlin’s rapid transit network reached an important milestone: for the first time, Berlin Hauptbahnhof is directly connected to the northern parts of the city by the suburban railway system. The new line initially operates as a shuttle service between Berlin Hauptbahnhof and Gesundbrunnen via Wedding and represents the first operational section of the long-planned S21 project.
Although the initial section covers only a few kilometres, it has considerable strategic importance for the network. It creates an additional north–south link, reduces pressure on existing interchange routes via Friedrichstraße, and provides the operational foundation for the future extension towards Potsdamer Platz and further south.
From terminal station to network hub
Berlin Hauptbahnhof opened in 2006 and is one of Europe’s largest railway stations. Despite its role as the city’s central hub for long-distance and regional services, it had lacked a direct connection to the north–south S-Bahn system until now. Passengers travelling from the northern districts previously had to change at Friedrichstraße or rely on regional trains.
The S15 closes this gap. The line connects Gesundbrunnen station on the northern ring directly with Hauptbahnhof. The journey takes only around five minutes, making the S15 the shortest regular S-Bahn line in Berlin.
The new connection is expected to improve access from the northern districts to the government quarter, the Hauptbahnhof and the city centre. Around 40,000 passengers per day are forecast to use the new service.
The first section of the S21 project
The S15 is not an isolated scheme, but the first operational section of the planned S21 north–south S-Bahn corridor. The project is intended to create a second north–south trunk route, complementing the historic north–south tunnel dating from the 1930s.
The first stage links the northern ring railway with Hauptbahnhof via Wedding. South of the Ringbahn, the route runs through a tunnel towards the central station. At Hauptbahnhof, a temporary S-Bahn platform has been constructed, connected to the main station building by a pedestrian bridge.
This temporary arrangement is necessary because the final S21 infrastructure will only be completed in later construction phases. The planned route will continue from Hauptbahnhof through the government district towards Potsdamer Platz. Later phases are intended to extend the line via Gleisdreieck towards Yorckstraße and Großgörschenstraße.
Infrastructure and operations
The S15 operates every ten minutes between Gesundbrunnen and Hauptbahnhof. The service initially runs as a dedicated shuttle operation, meaning that a full north–south through service is not required before the entire S21 corridor is completed.
The line serves three stations:
- Berlin Hauptbahnhof (temporary S-Bahn level)
- Berlin Wedding
- Berlin Gesundbrunnen
Wedding provides interchange with the U6 underground line and other S-Bahn services. Gesundbrunnen is already one of Berlin’s key transport hubs, offering connections to the Ringbahn, regional trains and several S-Bahn routes.
Rolling stock and technical requirements
The S15 uses standard Berlin DC S-Bahn rolling stock. The route operates within the Berlin S-Bahn system using third-rail electrification with 750 V DC.
Initially, Class 481 trains are deployed, while the newer Class 483/484 units may also be used in the future.
The vehicles must meet the specific requirements of the Berlin network:
- platform height of approximately 960 mm
- third-rail operation at 750 V DC
- restricted tunnel clearance
- high acceleration and braking performance for short station spacing
In tunnel operation, rapid passenger exchange is essential. Berlin’s S-Bahn trains therefore feature wide door areas and high acceleration capability to minimise dwell times.
Decades of planning
The delivery of the new connection took considerably longer than originally expected. Earlier plans envisaged a much earlier opening date, but complex construction conditions, technical modifications, supply issues and extensive testing and approval procedures caused significant delays.
Berlin’s geology presented particular challenges, especially in areas with soft ground and groundwater conditions. At the same time, the new infrastructure had to be integrated into an already heavily used railway system.
Importance for Berlin’s transport network
Although initially a short line, the S15 has an impact far beyond its physical length. The Hauptbahnhof now gains a direct connection to the northern ring railway, creating new travel patterns:
- Gesundbrunnen–Hauptbahnhof in around five minutes
- reduced pressure on the existing north–south route via Friedrichstraße
- improved accessibility of Hauptbahnhof from the northern districts
- foundation for further S21 construction phases
The opening therefore marks not only the introduction of a new S-Bahn line, but also the beginning of a long-term restructuring of Berlin’s suburban railway network. The S15 represents a move away from a historically developed radial system towards a more interconnected network with additional north–south capacity.
16.06.2026
