Which Major River Is NOT on the U.S. East Coast?

The Mississippi River is not an East Coast river. It flows through the central United States, draining 41% of the continental U.S., and empties into the Gulf of Mexico at Louisiana.

Actual East Coast Major Rivers

• St. Lawrence River — Northeast border, Great Lakes to Atlantic
• Hudson River — New York, tidal to Albany
• Delaware River — NY/PA/NJ/DE border, Philadelphia port
• Chesapeake Bay — Estuary of Susquehanna, Potomac, James, York rivers
• Potomac River — DC/MD/VA/WV border, Washington's river
• Susquehanna River — Longest East Coast river (444 mi), Chesapeake's main tributary
• Connecticut River — Longest in New England
• Savannah River — GA/SC border

The Mississippi's headwaters are in Minnesota; its basin covers the heartland. It defines the Midwest/West boundary, not the East Coast.