where does the saint johns river start and end
St. Johns River Starting in Indian River County and meeting the Atlantic Ocean at Duval County, the St. Johns is Florida's primary commercial and recreational waterway. It flows north from its headwaters, originating in the direction of the Lake Wales Ridge, which is only slightly elevated at 30 feet (9.1Â m) above sea level. Because of this low elevation drop, the river has a long backwater. It ebbs and flows with tides that pass through the barrier islands and up the channel.[8] Uniquely, it shares the same regional terrain as the parallel Kissimmee River, although the Kissimmee flows south.[2]
Saint Lawrence River The Saint Lawrence River begins at the outflow of Lake Ontario and flows adjacent to Gananoque, Brockville, Morristown, Ogdensburg, Massena, Cornwall, Montreal, Trois-Rivières, and Quebec City before draining into the Gulf of Saint Lawrence, the largest estuary in the world.[4] The estuary begins at the eastern tip of Île d'Orléans, just downstream from Quebec City.[2] The river becomes tidal around Quebec City.[5]