Supporters of the Treehouse at the Wall, a ramshackle structure built on a no man's land strip next to the Berlin Wall by Turkish guest worker Osman Kalin in 1983, fear it could be demolished by city authorities as a public safety hazard. They are rallying to save it, hoping it will become a memorial to the postwar foreign labourers who helped rebuild Germany.
A Symbol of Resistance
The treehouse, located on a small traffic island in Berlin's Kreuzberg district, has become a symbol of resistance, immigrant ingenuity, and the absurdity of cold war division. Kalin, who arrived in West Germany in the late 1960s, transformed a dump into a lush garden and built a two-storey structure around a mature tree trunk, defying East German authorities and winning permission to stay as long as it wasn't taller than the wall.
“Perhaps he wasn’t the perfect artist, but he created something artistic – something that became totally unique,” said Suat Özkan, general secretary of a Turkish community group in Berlin. Kalin, born in 1925 in Anatolia, was one of about 14 million guest workers who came to West Germany between 1955 and 1973. Nearly 3 million people of Turkish origin now live in Germany, about 200,000 in Berlin.
Fight for Preservation
After Kalin's death in 2018, his son Mehmet has maintained the property. Özkan argues the treehouse should serve as a memorial to the guest workers who contributed to Germany's postwar economic miracle, noting that no central memorial exists. Historian Stefan Zeppenfeld, author of a 2021 book on Turkish labourers in West Berlin, said the treehouse is “one of the few tangible legacies where we can actually see agency by Turkish guest workers as a real part of the cityscape.”
The city authorities, ahead of a Berlin election in September, are working with the community to address safety and legal concerns. Florian Schmidt, a Kreuzberg district councillor, said his office is cooperating with the Turkish community and Mehmet Kalin to “grant the necessary permits” for the structure to remain, while clarifying ownership issues.
Community Support
Adrian Sampson, of Alternative Berlin Tours, which highlights the city's subculture, said Kalin's story is about “resistance, community spirit and multiculture all together there.” He added, “I think it’d be an absolute shame, like really a pity for the city, because it just makes a lot of people happy.”
As a first step, Özkan is planning an open-air exhibition on the chain-link fence surrounding the treehouse, featuring archival pictures and Kalin's life story. The treehouse, with its mismatched planks, tongue-in-cheek Nato and Soviet flags, and a donated chandelier, remains a testament to one man's defiance and the enduring spirit of a city.
