The Texas Hill Country has fourteen major rivers, several of which have been dammed to form man-made lakes. These rivers provide reliable water supplies and recreational opportunities for the surrounding areas.

River Description
Blanco River The Blanco River originates from springs located three miles south of the Gillespie county line in northeastern Kendall County and flows southeast for eighty-seven miles, through Blanco and Hays counties to its confluence with the San Marcos River, inside the San Marcos city limits. Part of the Guadalupe River basin and The Blanco River has a drainage area of over 400 square miles.
Colorado River The Colorado River is the 18th longest river in the United States, and the longest river with both its source and mouth within Texas. The river flows generally southeast for 862 miles from Dawson County through Marble Falls, Austin, Bastrop, Smithville, La Grange, Columbus, and Bay City before emptying into the Gulf of Mexico at Matagorda Bay.
Devils River The Devils River is a intermittent, pristine, whitewater river in southwestern Texas, that southwest from its in northwest Sutton County for 94 miles through Val Verde County and empties into the northeastern shore of the Amistad Reservoir on the Texas/Mexico border near Del Rio. is one of the unspoiled rivers in the United States due to its remote location in a hostile environment which inhibits pollution from human and animal populations and also due to its path underground for part of its journey.
Frio River The name of the Frio River comes from the Spanish word for “cold,” and Frio County was named for this river. The river has three primary feeds – the East Frio River and the West Frio River, which rises from springs in northeastern Real County, join near the town of Leakey, and the Dry Frio River joins the main stream northeast of Uvalde. It flows generally southeast across central Uvalde and Frio counties and northeastern LaSalle, northern McMullen, and northwestern Live Oak counties for approximately two hundred miles from its sources until it empties into the Nueces River about a mile south of the town of Three Rivers.
Guadalupe River The Guadalupe River is one of the most beautiful rivers in Texas, extending from its source in western Kerr County to the Gulf of Mexico.
Lampasas River The Lampasas River originates sixteen miles west of the city of Hamilton and travels southeast for seventy-five miles through central Texas to a man-made reservoir called Stillhouse Hollow Lake. It continues for nine miles beyond the lake to a point where it converges with the Leon River to form the Little River near Belton. The river is characterized by low water levels most of the time, but is subject to flash flooding during periods of heavy rains.
Llano River The Llano River is a tributary of the Colorado River, which originates at the confluence of the North Fork and South Fork of the river near Junction, Texas and flows in east-northeasterly direction easterly the Hill Country in Central Texas to its mouth where it empties into Colorado River northwest of Austin.
Medina River The Medina River is located in Hill Country in the Edwards Plateau of south central Texas, surrounded by the beautiful and fertile Medina River Valley. The river begins at two separate springs in northwest Bandera County, Texas that form its north and west prongs which converge near Medina, Texas. The river is characterized by a distinctive greenish color of the water and is normally very shallow.
Nueces River The Nueces River is approximately 315 miles long and drains an area in central and southern Texas, from Real County southeastward into the Gulf of Mexico, of 16,800 square miles, with an annual runoff of some 620,000 acre-feet. It is the southernmost major river in Texas north of the Rio Grande, and was named Nueces, which is the Spanish word for nuts, because of the numerous pecan trees that the early settlers discovered along its banks.
Pedernales River The Pedernales River is a tributary of the Colorado River, that flows east for approximately 106 miles from springs in southeastern Kimble County, approximately 25 miles southeast of Junction  through the Texas Hill Country to its mouth where it flows into Lake Travis west of Austin. The name “Pedernales” comes from a Spanish word for the flint rocks characteristic of the riverbed, which was first used in the middle 18th century,
San Gabriel River The San Gabriel River is a river that flows through the Hill Country and Central Texas from the confluence of the North Fork San Gabriel and the South Fork San Gabriel  about 30 miles north of Georgetown, its mouth where it flows into the Brazos River northeast of college Station. Like many rivers in the Hill Country, the San Gabriel is subject to occasional but severe flooding.
San Marcos River The San Marcos River begins at San Marcos Springs which flow from the Edwards Aquifer into Spring Lake. Access to much of the headwaters is restricted due to the delicate ecosystem and numerous rare species. The upper river is a popular recreational area that flows through Texas State University and San Marcos. It is joined by the Blanco River after only four miles, and then flows through Luling and finally flows into the Guadalupe River near Gonzales after a total distance of 75 miles.
San Saba River The San Saba River is a is an undeveloped and scenic waterway located on the northern boundary of the Edwards Plateau, that begins in two primary branches and miles and drains an area of 3,150 square miles. The North Valley Prong rises four miles southeast of Eldorado in central Schleicher County and runs east through Schleicher County for 37 miles, while the Middle Valley Prong begins twelve miles northeast of Sonora in northern Sutton County runs 35 miles through the same county. These two prongs merge near Fort McKavett to form the San Saba River, which flows another 140 miles east/northeast until it drains into the Colorado River at the eastern edge of San Saba County, eight miles northeast of the town of San Saba.
Sanibal River The Sabinal River, originally called Arroyo de la Soledad – Spanish for “Stream of Solitude,” originates in fissure springs that flow from great slabs of limestone in the Lost Maples State Natural Area, seven miles north of Vanderpool in northwestern Bandera County, and flows generally south through Uvalde County for approximately 58 miles to its mouth, ten miles south of Sabinal where it joins the Frio River.