The Christmas Mountains are a small range of mountains next to Big Bend National Park in Brewster County, Texas, United States. The highest peak is above sea level. The 9,270 acre tract is owned by the Texas State University System and is open to the public and to academic researchers studying the area's natural resources. The area's shallow, stony soils support oak, juniper, mesquite, chaparral, various cacti, and grasses.