Photo #32519 - Point of Information - crossing Susquehanna River. Photo view looking at the river. The Susquehanna River, sixteenth largest river in America, is the largest river lying entirely in the United States that flows into the Atlantic Ocean. The Susquehanna and its hundreds of tributaries drain 27,500 square miles, an area nearly the size of South Carolina, spread over parts of New York, Pennsylvania, and Maryland. The river meanders 444 miles from its origin at Otsego Lake near Cooperstown, New York until it empties into the Chesapeake Bay at Havre de Grace, Maryland. Fredericksburg (Junction of I-78) to Pennsylvania/New York State Line