Tunnel 57 was a tunnel under the Berlin Wall that on 3 and 4 October 1964 was the location of a mass escape by 57 East Berlin citizens to West Berlin. It was built from the basement of an empty bakery at 97 Bernauer Straße in West Berlin, under the Berlin Wall – which at that time and place consisted of empty, bricked-up apartment buildings on the east side of Bernauer Straße – all the way to a disused outhouse in the rear courtyard at 55 Strelitzer Straße in East Berlin.