On the site of the historic Lehrter Bahnhof Europe’s largest station is presently under construction: This is where an east-west and a north-south InterCityExpress railway line intersect, combined with suburban and underground railway lines. The north-south track runs in a tunnel 15 m below ground level, passing below the Spree and the Tiergarten. The east-west track is located 10 m above street level.
The central design principle of the Lehrter Bahnhof is the prominent emphasis of the existing railway tracks in the urban landscape. Large filigree glass roofs as well as two bridging office buildings translate this principle with architectural means. In the central area of the station cross, which rests on a building socle, the ceilings of all levels are equipped with large openings, allowing daylight to penetrate as far as the underground platform levels, simultaneously ensuring a clear spatial orientation. Barrel vaults characterize the station hall located in a tunnel. The columns of these „vault tables“ are all centrally located on the platforms respectively between the railway tracks. The formal character of the cross vault ceil-ings in the north-south platform hall is also continued on the level above.
The 321 m long glass roof of the east-west hall is constructed as a lattice shell of almost square net elements varying in dimension, which are stiffened with steel ropes. In the south the roof surface is covered with photovoltaic modules. The glass roof construction was initiated simultaneously east and west of the north-south intersection. The first roof truss was mounted on February 1st, 2002, and two other trusses should follow each week. Work continued around the clock in three shifts, because the glass roof had to be completed for the date of the relocation of the railway tracks in June 2002. In order to keep this date, the roof was shortened by approximately 110 m on request of the client, resulting in a termination of the construction works before the original date. In this form the train station would remain a torso.
