Fifty-seven people escaped through the famous Berlin Wall tunnel known as Tunnel 57.
Tunnel 57 was dug in 1964 by a group of West Berlin students and helpers. The tunnel began in a disused bakery on Bernauer Straße and reached a building in East Berlin. It was named for the number of people who used it to escape before the route was discovered.
The tunnel was about 145 metres long and lay several metres below ground. Excavators worked under extreme secrecy because East German authorities actively searched for escape routes and informers could expose plans. The escapees included East Berlin residents who had been separated from relatives and friends by the border.
Tunnel 57 was one of many tunnel projects, but it became especially famous because of its scale and the number of successful crossings. Other tunnels failed, flooded, collapsed, or were discovered before they could be used. The story also appears in documentaries and historical accounts of divided Berlin.