Jack Browns Seaplane Base (FAA LID: F57) is a public-use seaplane base located 3 nautical miles (5.56 km) northwest of the central business district of Winter Haven in Polk County, Florida, United States. It is located on the northeast shore of Lake Jessie, which is part of the Winter Haven Chain of Lakes. The privately owned seaplane base is located adjacent to Winter Haven's Gilbert Airport and connected to it by an asphalt taxiway.