Underground station Unter den Linden is the interchange station for lines U5 and U6, and lies below the junction of Unter den Linden and Friedrichstraße. The platform of underground line U5 is underneath the central pedestrian promenade of Unter den Linden, and stretches from west of Friedrichstraße right up to Charlottenstraße. The U6 platform is directly below Friedrichstraße between Unter den Linden and Behrenstraße.
Three of the station entrances are on the central pedestrian promenade of Unter den Linden, one each to the west and east of Friedrichstraße and one west of Charlottenstraße. Two further entrances that lead directly to the U6 platform are located on Friedrichstraße, north of Behrenstraße.
Underground station Unter den Linden was designed by the architects Ingrid Hentschel and Axel Oestreich.
The architects previously designed underground station Brandenburger Tor and see strong links to the new underground station Unter den Linden. The design is therefore based on similar plans and employs the same materials: shell limestone for the walls, white terrazzo for the floors and black supporting columns in between.
Underground station Unter den Linden is designed as an interchange station for lines U5 and U6 and is spread over three levels. Line U6 runs at the top, while the middle level is a concourse where passengers can change between the two lines. Underneath, the U5 runs on the bottom level.
In cooperation with the adjacent Humboldt University, which is providing scientific images for an exhibition on the rear track walls, Unter den Linden underground station will be visually devoted to science.
The excavation pit for underground station Unter den Linden is built using the cut-and-cover top-down method. Diaphragm walls made of reinforced concrete initially provide support for the sides of the pit. Following this, a waterproof floor is constructed in the soil using jet grouting to form the bottom boundary of the pit. A cover is then concreted over the structure, minimising noise and dust pollution. The two main tunnels will be built by boring through this pit.
Inside the pit, the soil is excavated and the reinforced concrete floor and walls of the structure as well as intermediate ceilings are built. The main tunnels will be broken off within the station itself.
Once the basic structure is complete, finishing and completion is carried out: gravel is poured in, the tracks are laid and all technical cabling required for underground operation is installed. Lifts and escalators are also added. The interior design envisaged by the architects for the floors, walls and lighting is then completed. In a final step, facilities typical of a Berlin underground station such as ticket machines, ticket-cancelling posts and information displays are installed.
Length: 152 metres
Depth: up to 17 metres
U5 platform depth: 14 metres
U6 platform depth: 5 metres
Preliminary works contractor: Implenia
Finishing works continue on all levels. Passengers of the U6 can have quick views of the construction site because the works are being done during active operation.
Visualization of underground station Unter den Linden
The exhibition. Six years of building the U5 gap closure.
Unter den Linden, summer 2017