This artwork on the corner of Bernauer Straße and Strelitzer Straße in Berlin, Germany, represents a watchtower used by East German border guards before the fall of the Berlin Wall.
It’s made from four iron girders, and when you stand between them and look up you see a perfect square.
Although the watchtower is long gone, the girders give an eerie impression of its size. It’s like stepping into a ghost building.
