Hamburg's WWII flak tower revived as green oasis

A huge concrete colossus dominates the city skyline, right in the heart of Hamburg's St. Pauli district. Also known as the Media Bunker or, more recently, the Green Bunker, the World War II relic has become the new landmark. Fifty meters (164 feet) in height, the building is one of Germany's few surviving flak tower complexes.

A 560-meter landscaped walkway has been added around the outer wall of the former anti-aircraft bunker, its ramps and stairs leading up to the roof. At the top, a new garden of around 1,400 square meters (15,000 square feet) supporting some 23,000 plants will turn the bunker into a natural oasis in the city, with the greenery acting as a natural air-conditioning system.

Critics have already said the gray, concrete bunker isn't green enough. But a spokesperson for the developer Matzen Immobilien rejected the accusations at the opening event in early July, saying the plants still needed time to grow. “Of course, the final overall impression will only be created when the trees and the climbing plants have reached their intended size," the spokesperson said.

Originally 38 meters in height, the bunker has grown by five stories in recent years. In addition to the path and the roof garden, the bunker now boasts a hotel, restaurants and a new multipurpose hall for sports and cultural events. A memorial has also been added, detailing the history of the bunker, which was built by forced laborers in 1942.

During World War II, the bunker was one of Hamburg's two flak towers and was primarily used for air defense. Sources show that up to 25,000 people found shelter in the bunker at times during the bombing of the city.

After the war, creative minds took over the bunker. In December 1952, Norddeutscher Rundfunk, then still NWDR, broadcast the first daily news show from the site. The smaller command and control bunker (seen here at left) was demolished by 1974.

The Allies wanted to blow up the city's bunkers after the end of the war, but the bunker in St. Pauli was preserved due to its massive construction. It was eventually designated as a protected building, and soon became a creative center housing art and culture groups.

The latest chapter in the bunker's history saw the addition of the five pyramid-like stories and the creation of the "hanging gardens of Hamburg," which are being monitored by landscape scientists. The €60-million ($65.8-million) renovation serves as an example of climate adaptation and sustainable urban planning to cities around the world.

A glance downwards can make some people feel dizzy. The walkway, up to 6 meters wide, starts at ground level on the north side of the bunker. It continues to ascend via the east, south and west facades. Finally, at a height of 58 meters, the path leads into the public city garden.

From the roof garden, visitors are treated to an impressive 360-degree panoramic view of the Hanseatic port city. Many of Hamburg's landmarks and famous buildings are visible from the top — especially the nearby Millerntor Stadium, home to the FC St. Pauli soccer club.

Hardly any other place in Hamburg offers a more exciting view of tourist attractions such as the Elbphilharmonie, the Michel and the harbor. Up to 900 people can visit the garden at the same time.