Until late in the 19th century the Caloosahatchee River was fed by a series of lakes starting from Lake Hicpochee, and including Lettuce Lake, Bonnet Lake and Flirt Lake. A waterfall and set of rapids at the lower end of Flirt Lake marked the beginning of the river. The rapids were close to 1 mile (1.6 km) long, with a drop in elevation of about 10 feet (3.0 m).