The St. Marys River (or St. Mary's River) may refer to:

• The St. Marys River (sometimes spelled as St. Marys River) is a river, approximately 22 mi (35 km) long, in southern Maryland in the United States. It rises in southern St. Marys County, and flows SE through Great Mills, widening into a tidal estuary near St. Marys City... St. Marys River in State nickname: Old Line State; Free State Other U.S. States Capital Annapolis Largest city Baltimore Governor Robert L. Ehrlich Official languages English Area 32,160 km² (42nd)  - Land 25,338 km²  - Water 6,968 km² (21%) Population (2000)  - Population 5,296,486 (19th)  ... Maryland in the United States.
• The St. Marys River (sometimes spelled as the St. Marys River) is a river, approximately 90 mi (144 km) long, in the southeasern United States. For its entire length, it forms the eastern portion of the boundary between the U.S. states of Georgia and Florida. It rises in... St. Marys River separating State nickname: Peach State / Empire State of the South Other U.S. States Capital Atlanta Largest city Atlanta Governor Sonny Perdue Official languages English Area 154,077 km² (24th)  - Land 150,132 km²  - Water 3,945 km² (2.6%) Population ( 2000)  - Population... Georgia and State nickname: Everglade State, Sunshine State Other U.S. States Capital Tallahassee Largest city Jacksonville Governor Jeb Bush Official languages English Area 170,451 km² (22nd)  - Land 137,374 km²  - Water 30,486 km² (17.9%) Population (2000)  - Population 15,982,378 (4th)  - Density... Florida in the The United States of America — also referred to as the United States, the U.S.A., the U.S., America¹, the States, or (archaically) Columbia — is a federal republic of 50 states located primarily in central North America (with the exception of two states: Alaska and Hawaii... United States.
• The St. Marys River is a tributary of the Maumee River, approximately 100 mi (161 km) long, in western Ohio and eastern Indiana in the United States. It drains a primarily rural farming region in the watershed of Lake Erie. It is formed in southern Auglaize County in western Ohio... St. Marys River in State nickname: The Hoosier State Other U.S. States Capital Indianapolis Largest city Indianapolis Governor Mitch Daniels Official languages English Area 94,321 km² (38th)  - Land 92,897 km²  - Water 1,424 km² (1.5%) Population (2000)  - Population 6,080,485 (14th)  - Density 65... Indiana in the United States.
• The St. Marys River (sometimes spelled as the St. Marys River) drains Lake Superior, starting at the end of Whitefish Bay and flowing 120 km southeast into Lake Huron. For its entire length it is an international border, separating Michigan in the United States from Ontario, Canada. The most... St. Marys River is a river connecting The Great Lakes from space; Lake Superior is on the upper left Lake Superior is the largest of North Americas Great Lakes. It is the largest freshwater lake in the world by surface area with Lake Baikal in Siberia having more volume. (The Caspian Sea is larger, but contains... Lake Superior and The Great Lakes from space; Lake Huron is the third from the left. Lake Huron is one of the five Great Lakes of eastern North America, and separates Michigan from Ontario. Georgian Bay, the easternmost part of Lake Huron, is entirely within Canada. Lake Huron is separated from Lake Michigan... Lake Huron, flowing between State nickname: Wolverine State or Great Lakes State Other U.S. States Capital Lansing Largest city Detroit Governor Jennifer Granholm Official languages English Area 250,941 km² (11th)  - Land 147,255 km²  - Water 103,687 km² (41.3%) Population ( 2000)  - Population 9... Michigan and Motto: Ut Incepit Fidelis Sic Permanet (Loyal she began, loyal she remains) Other Canadian provinces and territories Capital Toronto Largest city Toronto Lieutenant Governor James K. Bartleman Premier Dalton McGuinty (Liberal) Area 1,076,395 km² (4th)  - Land 917,741 km²  - Water 158,654 km² (14.7%) Population... Ontario.

See also The Saint Mary River is a tributary of the Saskatchewan River. The river together with the Belly River and Waterton River drains a small portion of Montana to the Hudson Bay watershed. The river rises as a stream on Gunsight Mountain in Glacier National Park and flows into Gunsight Lake... St. Mary River