The Myakka River is a river in southwestern Florida. It arises near the Hardee-Manatee county line and flows southwest and then southeast through Manatee, Sarasota and Charlotte counties to Charlotte Harbor, an arm of the Gulf of Mexico. The river is 72 miles (116 km) long and has a drainage basin of 602 square miles (1559.2 km2), of which 314.7 square miles (815 km2) lies in Sarasota county. The last 20 miles (32 km) of the river is tidal and brackish.