In cooperation with Deutsche Bahn, the centrally located main railway station in Frankfurt am Main is to be developed into an intermodal transport hub. The railway junction in Frankfurt is one of the most heavily used transport hubs in Deutsche Bahn's rail network. However, it is already reaching the limits of its capacity. As a result, trains sometimes have to wait until another train has cleared the track before entering Frankfurt Central Station. This results in delays. A long-distance railway tunnel, which is planned under the historic main station, will create additional platforms that can be used by local and long-distance trains and connect them to the existing above-ground tracks, thus increasing the capacity for long-distance and local transport and making traffic flows smoother in future. From a functional point of view, the design is expected to create an efficient flow of people to trams, buses and taxis. With a planned depth of 40 metres under the south side of the main station, the design poses particular challenges in terms of construction and design. The overall aim of the design task is to create an attractive and sustainable intermodal transport hub in the heart of the city of Frankfurt with an extended range of commercially usable areas while preserving the historic railway station building, which is convincing from an architectural and urban planning perspective.