Beginning in 1976, the Wall was refurbished with prefabricated cement panels that went by the product name “Border Wall 75.” The result was a gigantic, continuous cement surface on the Western side that offered graffiti artists an enormous space for creative activity. Soon enough the Wall was regarded as the world’s largest canvas. On the Eastern side, GDR border troops employed a multi-layered system of barricades to make sure that potential escapees were kept as far from the actual Wall as possible. In 1984, the “Haus am Checkpoint Charlie” (“House at Checkpoint Charlie”), a museum dedicated to the Wall, initiated an art project called “Overcoming the Wall by Painting It.” In October 1986, as part of this project, American artist Keith Haring (1958–1990) used the German national colors to paint a human chain on a section of the Wall. As these photos suggest, his work was observed with great interest by a GDR border guard on the other side. Photos by Oskar Dahlke.