For twenty-eight years the complex and constantly evolving border fortification known simply as 'The Berlin Wall' divided the city. Although much of it was removed, hundreds of remnants and traces still exist to show where the border was and how it worked. This guide was written on the basis of a complete documentation of the extant remnants and traces of the Wall which the authors produced in 2001-2003 for the Berlin Senate Department for Urban Development. It offers an entirely new view of an absurd but historically unique border.