Delays in the Karlsruhe car tunnel construction persist, with projected completion pushed back to October.

Construction work causing extensive traffic disruptions in Karlsruhe's car tunnel, necessitating detours and a lot of patience from motorists.

, and Administrator

2025 September 16 . 8:51 PM

2 min read

Delays at Karlsruhe's car tunnel construction site extend until October

Delays in the Karlsruhe car tunnel construction persist, with projected completion pushed back to October.

The Schlossplatz tunnel, a vital connection between the east and west of Karlsruhe's city center, is currently undergoing a significant renovation. Built in 1964/1965, the tunnel was initially planned for modernization, but the passage of time has revealed unforeseen challenges.

Over the decades, road salt seepage has left deep marks on the concrete and steel reinforcement. To address this, large areas of concrete have had to be removed, and exposed steel bars have been replaced and protected with sprayed concrete. This extensive repair work is necessary to ensure the tunnel's structural integrity.

The renovation, which began in late June 2021, has led to several changes for users of the tunnel. The main driving lanes have been closed, and the speed limit has been reduced to 30 km/h. Taller vehicles must stay outside the tunnel, as only vehicles that are no higher than two meters are allowed to pass. Access to the Schlossplatz tunnel is currently limited to the east.

The initial plan was to reopen at least part of the lanes by the end of October 2025, but additional delays are possible. The expected end date for restrictions in the Schlossplatz tunnel is now the end of 2026, but this date is uncertain due to the severity of the damage and potential additional work.

The responsibility for the execution of the renovation lies with DB InfraGO, which expects the work to be completed by the end of 2026 but has not yet announced a final date. The Schlossplatz tunnel, upon its completion, will once again serve as a crucial link, providing access to several car parks and relieving the market square.

The renovation has caused stress for Karlsruhe residents for weeks due to closures and detours. As the city navigates this temporary inconvenience, it looks forward to the future, when the Schlossplatz tunnel will once again be a vital part of its urban landscape.