Our Pick
Posted on @rawstates
Fort Zachary Taylor holds for the Union
1861
Key West, Florida
Public domain · Wikimedia Commons
Florida seceded, but a Union captain marched his men into this fort at night before anyone organised to stop him, and Key West stayed federal for the whole war. The blockade squadron worked out of it and took hundreds of ships. Its lower casemates were later filled with sand and forgotten, which is why the largest cache of Civil War cannon in the country was found buried here in the 1960s.
That was 1 of the hidden places.
Location: documented spot
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