<P> The Trans - Pecos Natural Region has less than 12 inches ( 300 mm ) annual rainfall . The most complex Natural Region , it includes Sand Hills , the Stockton Plateau , desert valleys , wooded mountain slopes and desert grasslands . The Basin and Range Province is in West Texas , west of the Pecos River , beginning with the Davis Mountains on the east and the Rio Grande to its west and south . The Trans - Pecos region is the only part of Texas regarded as mountainous and includes seven named peaks in elevation greater than 8,000 feet ( 2,400 m ) . This region includes sand hills , desert valleys , wooded mountain slopes and desert grasslands . The vegetation diversity includes at least 268 grass species and 447 species of woody plants . National Parks include the Amistad National Recreation Area , Big Bend National Park , Chamizal National Memorial , Fort Davis National Historic Site , Guadalupe Mountains National Park , and the Rio Grande Wild and Scenic River . This area is part of the Chihuahuan Desert . </P>
<P> The Trans - Pecos Natural Region has less than 12 inches ( 300 mm ) annual rainfall . The most complex Natural Region , it includes Sand Hills , the Stockton Plateau , desert valleys , wooded mountain slopes and desert grasslands . The Basin and Range Province is in West Texas , west of the Pecos River , beginning with the Davis Mountains on the east and the Rio Grande to its west and south . The Trans - Pecos region is the only part of Texas regarded as mountainous and includes seven named peaks in elevation greater than 8,000 feet ( 2,400 m ) . This region includes sand hills , desert valleys , wooded mountain slopes and desert grasslands . The vegetation diversity includes at least 268 grass species and 447 species of woody plants . National Parks include the Amistad National Recreation Area , Big Bend National Park , Chamizal National Memorial , Fort Davis National Historic Site , Guadalupe Mountains National Park , and the Rio Grande Wild and Scenic River . This area is part of the Chihuahuan Desert . </P>
which region in texas has the highest elevation
which region in texas has the highest elevation
The Trans - Pecos region
The Trans - Pecos region