The former anti-aircraft bunker, one of the largest high-rise bunkers in Germany with a floor area of 75 x 75 metres, has been extended by five pyramid-shaped storeys to a height of 58 metres, inspired by concept of INTER±POL Interdisziplinäre Studios GmbH. A 560-metre-long green mountain path leads up to the roof via ramps and stairs. In total, more than 7,600 square metres of public and communal green areas have been created, with an additional 1,700 square metres of façade greening. Some 4,700 plants make the bunker a natural oasis in the city, designed by Landschaftsarchitektur+ in collaboration with Mark Krieger and Ingrid Gock.
For this unique project, it was particularly important to take into account the specific features of the site. Due to the exposed location of the city garden on top of the bunker’s new 5-storey roof structure, the trees and shrubs had to be not only drought and frost resistant, but also wind resistant. The trees selected and supplied by the Lorenz von Ehren nursery included Acer campestre, Malus domestica ‘Weißer Winterglockenapfel’, Pinus sylvestris, Acer neglectum ‘Annae’, as well as various shrubs, climbers, hedges, and overhanging shrubs.
The green roof and façade of the World War II-era building act as a natural air-conditioning system for the entire complex, which includes a hotel, event locations, rooms for social and cultural projects (by Hilldegarden e.V.) and much more. This pioneering landscape architecture project is also scientifically monitored. More than 60 sensors collect data on how the various plants affect the microclimate (humidity, temperature, etc.) in their respective locations.
