Fleet Post Office, a postal system used by the U.S. Navy and Coast Guard for mail delivery to ships and overseas military installations.
Military acronym from 'Fleet Post Office', established during World War II to handle mail for naval vessels at sea. The system evolved from the need to maintain communication between military personnel and home.
FPO addresses are fascinating because they represent mail floating somewhere on the ocean - your letter might reach a sailor in the Pacific or Mediterranean, but the postal code gives no geographic clue. It's a reminder of how military logistics adapt civilian systems for extraordinary circumstances.
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