Two major cities are located along the Savannah River: Savannah, and Augusta, Georgia. They were the center of early English settlements during the Colonial period of American history. The Savannah River is tidal at Savannah. Downstream from there, the river widens into an estuary. Then it flows into the Atlantic Ocean. The area where the river's estuary meets the ocean is known as "Tybee Roads". The Intracoastal Waterway flows through a section of the Savannah River near the city of Savannah.