The Texas Blind Salamander, is known to exist in the upper part of Hays County. Recommended as potential component of National Wild and Scenic Rivers System. River Recreationist Survey ranked it 5th as state recreational river. LBJ State Park is adjacent to river near Stonewall. Pedernales Falls State Park provides access to Pedernales Falls, a major waterfall.
River is spring-fed with many limestone formations and bluffs.
Cypress Canyon-Hamilton's Pool is a significant natural area. In this area, near-unique survival conditions exist for many Edwards plateau species. West Cave Canyon is the most beautiful spot in central Texas. Bald cypress, red columbine and native orchids grow along the river, which provides habitat for abundant wildlife. Red River, Prairie Dog Town Fork Hall, Brisco, Armstong, Randall Highway 70 crossing at Briscoe-Hall County Line upstream to Lake Tanglewood.