<Tr> <Th_colspan="2"> Basin features </Th> </Tr> <Tr> <Th> Basin size </Th> <Td> 4,180 sq mi (10,800 km) </Td> </Tr> <P> The San Antonio River is a major waterway that originates in central Texas in a cluster of springs in midtown San Antonio, about 4 miles north of downtown, and follows a roughly southeastern path through the state . It eventually feeds into the Guadalupe River about 10 miles from San Antonio Bay on the Gulf of Mexico . The river is 240 miles long and crosses five counties: Bexar, Goliad, Karnes, Refugio, and Wilson . </P> <P> The first documented record of the river was from Álvar Núñez Cabeza de Vaca on his explorations of Texas in 1535 . The river was later named after San Antonio de Padua by the first governor of Spanish Texas, Domingo Terán de los Ríos in 1691 . </P>

Where does the san antonio river start and end
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