<Tr> <Th> Length </Th> <Td> 229 mi (369 km) </Td> </Tr> <Tr> <Th> Basin </Th> <Td> 3,980 sq mi (10,308 km) </Td> </Tr> <P> The Meramec River (/ ˈmɛrɪmæk /) is one of the longest free - flowing waterways in Missouri, draining 3,980 square miles (10,300 km) while wandering 218 miles (351 km) from headwaters near Salem to where it empties into the Mississippi River near St. Louis at Arnold and Oakville . The Meramec watershed covers six Missouri Ozark Highland counties--Dent, Phelps, Crawford, Franklin, Jefferson, and St. Louis--and portions of eight others--Maries, Gasconade, Iron, Washington, Reynolds, St. Francois, Ste . Genevieve, and Texas . Between its source and its mouth, it falls 1,025 feet (312 m). Year - round navigability begins above Maramec Spring, just south of St. James . The Meramec's size increases at the confluence of the Dry Fork, and its navigability continues until the river enters the Mississippi at Arnold, Missouri . </P> <P> The first European explorer was French Jesuit priest Jacques Gravier, who traveled the river in 1699--1700 . The name likely means' the river of ugly fishes' or' ugly water' in Algonquian . Early variant spellings of the name were Mearamigoua, Maramig, Mirameg, Meramecsipy, Merramec, Merrimac, Mearmeig, and Maramecquisipi . Early on, the river became an important industrial shipping route, with lead, iron, and timber being sent downstream by flatboat and shallow - draft steamboat . </P>

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