Islands off the southern coast of Florida. The best known are Key Largo and Key West.
island chain, Monroe and Miami-Dade counties, southern Florida, U.S. Composed of coral and limestone, the islands curve southwestward for about 220 miles (355 km) from Virginia Key in the Atlantic Ocean (just south of Miami Beach) to Loggerhead Key of the Dry Tortugas in the Gulf of Mexico. Bodies of water between the keys and the mainland include Biscayne and Florida bays
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