HOCHBAHN's goal is to bundle as many measures as possible in order to make the most of the 14-month interruption in service between Baumwall and Hauptbahnhof. The heart of the project is the complete renewal of the subway trough, i.e. the tunnel exit of the U3, at Mönkedamm.

Almost all project components are subject to monument protection. This and the tight underground and above-ground construction environment demand special care. Investments in the refurbishment and barrier-free expansion of the U3 in the city center total around 86 million euros.

By 2022, all subway stops in the central downtown area will be barrier-free.