a mostly inland water route, partly natural and partly artificial, extending 1550 miles (2500 km) along the Atlantic coast from Boston to Florida Bay (Atlantic Intracoastal Waterway) and 1116 miles (1800 km) along the Gulf coast from Carrabelle, Fla., to Brownsville, Tex. (Gulf Intracoastal Waterway): constructed to protect small craft from the hazards of the open sea.
