This dissertation proposal studies the potential of the Berlin Wall. With the opening of the border between East and West Berlin on the 9th of November 1989, the Berlin Wall lost its meaning and suddenly became a void cutting through the centre of Berlin. It provided a unique historical condition and opportunity to rethink the problem of the void, the edge and the potential of separation that would not just revert to urban connection and filling, or, the romanticised notion of separation that Rem argued for. The wall raises the question of what kind of alternative urbanism can be envisioned, a system capable of providing for development and programmatic insertion, yet retaining the different characters of the existing edges and voids. A new strategy of the linear.