East German soldiers, left, set up barbed-wire barricades at the border separating East and West Berlin on August 13, 1961. West Berlin citizens, right, watch the work. #

A young East Berliner works on a concrete wall that was later topped by barbed wire at a sector border in the divided city on August 18, 1961. People’s Police stand guard in the background as another worker mixes cement. #

Under the eye of a Communist "People's Policeman," East Berlin workers with a power shovel destroy one of a number of cottages and single-family houses along a sparsely settled stretch of the east-west Berlin boundary in October 1961. #

Tracks of the Berlin elevated railroad stop at the border of the American sector of Berlin in this air view on August 26, 1961. Beyond the fence, the Communist-ruled East Berlin side, the tracks have been removed. #

Workers set up a sign warning pedestrians they are leaving the American sector of Berlin, Germany, on Wiener Strasse (Vienna Street) in the district of Kreuzberg in West Berlin, on August 13, 1961. In the background is the Berlin Wall that divides East and West Berlin. #

Russian (background) and American (foreground) tanks face each other at the Friedrichstrasse checkpoint in Berlin during the construction of the Berlin Wall on October 28, 1961. #

A young girl gazes pensively through the pane of her apartment window, which reflects the image of barbed wire fencing that tops the nearby Berlin Wall, in December 1962. #

After East Germans jumped to freedom in the West, the windows of this building on the eastern side of the wall were bricked over. The building was later demolished. Photographed in 1962. #

One of six West Berliners who dug a 20-inch-wide tunnel under a border street to East Berlin crawls out sometime over the weekend of June 8–10, 1962. Sixteen East Berliners, relatives of the diggers, came through the tunnel dragging an infant behind them in a wash basin. The tunnel was believed to have been discovered in early June 12, a few hours after the 17 reached the West. #

A 75-year-old woman is helped into Tunnel 57, through which 57 East Berlin citizens escaped to the western sector of the city on October 3 and 4, 1964. The tunnel was dug from West to East by a group of 20 students led by Joachim Neumann, from a disused bakery building on Bernauer Strasse, under the Berlin Wall, to a building 145 meters away on Strelitzer Strasse in East Berlin. #

Original caption: "To give the impression of normality, East German authorities sent children to the base of the Berlin Wall to act as if they were at play. Berlin, 1962." #

A dying Peter Fechter is carried away by East German border guards who shot him down when he tried to flee to the West in this August 17, 1962, photo. Fechter was lying in no-man's-land for 50 minutes before he was taken to a hospital, where he died shortly after his arrival. #

President John F. Kennedy stands before a huge crowd in West Berlin on June 26, 1963. Here he made his famous declaration: "Ich bin ein Berliner," and pledged support to West Berlin against Communist threats. #

A photograph taken on August 10, 1966, of the system of walls, barriers, watchtowers, and an open "death strip," along the border separating East and West Berlin, looking toward the Brandenburg Gate, as seen from the German Reichstag Building. #

East German border guards carry away a refugee who was wounded by East German machine-gun fire as he dashed through Communist border installations toward the Berlin Wall in 1971. #

In this photo taken on August 11, 1988, the year before the Berlin Wall came down, a message is seen painted on the wall at Potsdamer Platz: "Berlin will be wall-free." A little more than a year later, on November 9, 1989, the wall finally came down. #