Before construction could begin, the ground was systematically investigated. The focus was not only on load-bearing capacity but also on possible contamination. The site had a turbulent history: after several changes of use, it was heavily bombed during the Second World War. Bomb craters up to six meters deep were often backfilled in the post-war years with rubble, debris, or even remnants of munitions. Contamination, especially in the upper soil layers, therefore could not be ruled out. These analyses formed a crucial basis for further planning and helped to minimize p
Clearing the Construction Site: From urban wasteland to construction site
Necessary: soil tests
Utility Lines: What Ran Underground?
Beneath the future building site ran a dense network of utility lines – for electricity, water, and district heating. These first had to be carefully mapped, documented, and then either relocated or decommissioned. Special care was required, as some lines were directly connected to neighboring buildings such as the Philharmonie and the Neue Nationalgalerie. Only once all technical systems had been reorganized could the site be fully cleared and prepared for construction. This work was therefore just as fundamental to the progress of the project as the soil investigations themselves.
In 2020, the preparatory measures for site clearance began. A central step was the excavation of the construction pit: around 16 meters deep and approximately 8,000 m² in size. By spring 2023, about 130,000 m³ of soil had been removed and transported away.
To secure the construction pit, a watertight trough structure was installed. Around 25-meter-deep reinforced concrete diaphragm walls, about 500 anchors, and a jet-grouting base with roughly 1,000 micropiles stabilized the ground and at the same time ensured the protection of the surrounding buildings such as the Neue Nationalgalerie and the Philharmonie.
With the completion of this work, the foundation was laid for the ceremonial setting of the cornerstone on February 9, 2024 – a significant milestone for the project. The site clearance thus marked the beginning of construction work for the new Museum of the 20th Century at the Kulturforum.
Further information on the laying of the foundation stone, construction progress, and the ongoing building phase can be found on the Construction Phase page.
Several sculptures from the collection of the Nationalgalerie were located on the site. They were dismantled and stored before construction began and will be reinstalled in a suitable location once the new building has been completed.