New train station in Berlin

Soon after the fall of the Berlin Wall in 1989, city planners began work on a transport plan for reunified Berlin. One element of this became the “Pilzkonzept” (mushroom concept), in which a new north-south railway line intersecting the Stadtbahn was to be constructed. The name derived from the shape formed by the new line and existing lines, which vaguely resembles a mushroom.

In June 1992 the federal government decided that the new station should be built on the site of Lehrter Bahnhof. While close to the centre of Berlin and government buildings, the area was still not heavily populated. The following year, a design competition for the project was held, which was won by the Hamburg architecture firm Gerkan, Marg and Partners.

The design called for traffic on five levels. The highest is the main deck, including two S-Bahn platforms, on a bridge 10 m above street level, and the lowest comprises four platforms 15 m underground. New tunnels to Potsdamer Platz under the Spree and the Tiergarten, Berlin’s central park, form a new north-south line running to the northern part of the S-Bahn ring around central Berlin. Platforms for the planned extension to U-Bahn line 5 are also included, as were platforms for the cancelled Transrapid maglev train. The short line U55 should open in 2007.

The building work took place in several stages. In 1995 the construction of the Tiergarten tunnels began, and this work was finished in 2005 with the completion of the last station tunnel. The tunnels provide four tubes for long-distance and regional services and two tubes in a separate alignment for the U-Bahn, in addition to a road tunnel ventilated by a 60-m-high tower completed in 2004. During its construction, the course of the Spree had to be diverted (1996-1998). Water leaks in the tunnels caused over one year’s delay to the construction work.