The Big Bend is part of the Trans-Pecos region in southwestern Texas, United States along the border with Mexico, north of the prominent bend in the Rio Grande for which the region is named.
[1] Here the Rio Grande passes between the Chisos Mountains in Texas and the Sierra Madre Oriental in Mexico as it changes from running east-southeast to north-northeast.
In Mexico, adjacent areas of protected lands on the south side of the Rio Grande include the Cañón de Santa Elena Flora and Fauna Protection Area (ca.
850,630 acres), and the Maderas del Carmen Flora and Fauna Protection Area (ca.
The largest towns in the region are Alpine, Presidio, Marfa, Sanderson, Terlingua, and Marathon.