Our Pick
Posted on @rawstates
Arlington Hall, the girls' school that became the Army's codebreaking headquarters
1942
Arlington, Virginia
Public domain · Wikimedia Commons
The building went up as a private girls' school and was taken over during the Second World War as the home of the Army's Signal Intelligence Service. Most of the codebreaking staff working here were women recruited straight out of college and schoolteaching. The site is still federal, holding the State Department's foreign affairs training centre and an Army National Guard readiness centre.
That was 1 of the hidden places.
Location: historic site
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