The Amerika Gedenkbibliothek public library (America Memorial Library, left) was opened in 1954 in West Berlin facing the East. Before the Berlin Wall was erected in 1961 many people were able to travel freely between East and West Berlin. The Gedenkbibliothek was built, in part, with American money and was used as a Cold War era soft-power tool to highlight the West's open and free access to books and information, freedoms denied to the people of Soviet-controlled East Berlin. In response, East Germany built the elegant Berliner Stadtbibliothek library (Berlin City Library, right) in East Berlin. Formerly, these two libraries were on opposite sides of the Berlin Wall, front line of the Cold War and one of the most troubled borders on Earth.