The Nueces River is a river in the U.S. state of Texas, approximately 315 miles (507 km) long. It drains a region in central and southern Texas southeastward into the Gulf of Mexico. It is the southernmost major river in Texas northeast of the Rio Grande. The Nueces rises northwest of San Antonio in the Edwards Plateau, in Real County approximately 50 mi (80 km) north of Uvalde. It flows south through the Texas Hill Country, past Barksdale and Crystal City, approaching to within 35 mi (56 km) of the Rio Grande on the border with Mexico.