Grüner Bunker (St. Pauli Flakturm) by Interpol Studios, phase10, and Landschaftsarchitektur+ is a monument transformation and vertical extension project of 2024 in Germany, Hamburg. While use before did serve as a Nazi-era anti-aircraft turret (Flakturm IV) and later a "media bunker" for clubs and offices, the transformation of 2024 provided five additional floors housing a hotel, a sports hall, and a 560-meter public "mountain path", increasing the usable surface area from the original 38-meter high monolith to a densified landmark featuring a 1,400 m² public roof garden.
This project contributes to the social-ecological transformation by converting a symbol of wartime oppression into a "climate lighthouse" that utilizes massive vertical and rooftop greening to mitigate the urban heat island effect. By adding 16,000 perennials and 4,700 trees to the historic concrete structure, it creates a unique biodiversity corridor and public park in a dense neighborhood, while serving as a long-term research site for urban microclimate improvement.
Hamburg
Germany
Military
Hotel, Restaurant, Concert Hall, Roof Top Park
1942
2025