Nestled in the intracoastal waterways between Riviera Beach and Palm Beach Shores, you'll find Peanut Island, which features a no-longer-secret bomb shelter which was built in 1960 to be President John F. Kennedy's "safe place" in the event of nuclear war. Nowadays it's mostly a gigantic park, with camping and fishing piers.
Originally named Inlet Island, it was renamed for a planned peanut oil operation which went bankrupt in 1946 before reaching fruition.
There are no roads to Peanut Island, but you can take Capt. Joe's Peanut Island Water Taxi. There are also no restaurants or bars on the island - not even a snack vending machine - so, like the Boy Scouts say, be prepared.