Open architecture : migration citizenship and the urban renewal of Berlin Kreuzberg by IBA 1984 87 The International Building Exhibition 1984 87 in Berlin constitutes one of the most remarkable examples to discuss open architecture . Almost 10 000 dwellings were constructed or restored in the Kreuzberg districts adjacent to the Berlin Wall inhabited about halfway by immigrants. The renowned author Esra Akcan related in many ways to Turkey Berlin and the USA narrates the history and reverberations of this architectural political event