Atlantic Beach, in Duval County, grew from Henry Flagler's Mayport branch railroad, built in 1900 with a station near today's Adele Grage Cultural Center. Flagler and Isaac George soon built the Continental Hotel on the line between Pablo Beach and Mayport, a summer resort with 250 rooms, a dance pavilion, tennis courts and a fishing pier.
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In 1913 the railroad sold most of the land to the Atlantic Beach Corporation, which paved streets and installed lights, water and sewer lines, and the hotel was renamed the Atlantic Beach Hotel. During World War I people feared the coast, the corporation went bankrupt and the hotel burned on September 20, 1919. Land sales revived after the war.
The Town of Atlantic Beach was incorporated in 1926, and its first charter, drafted by Isaac George, was adopted in 1929. The first town hall burned in 1932 and was rebuilt that year. The new Mayport Naval Station and the Mathews Bridge spurred later growth, and the town expanded its boundaries in 1987. When most of Duval County consolidated with Jacksonville in 1968, Atlantic Beach remained independent.
Sources
Wikipedia: Atlantic Beach, Florida