LSR was an acronym for an air-raid shelter (Luftschutzraum). During the later part of the war LSR received a new meaning and became "Lernt schnell Russisch" - or "Learn Russian quickly."
Converted Air-Raid Shelter
This bunker, near the Friedrichstrasse rail station in Berlin Mitte, was built in 1942. It was designed to give passengers from the Friedrichstrasse railway station protection against Allied air raids. The shelter now holds a collection of contemporary art on the lower level and a private home on the top.