Brewster County, the largest county in Texas, is located in the Trans-Pecos region of West Texas, and is the site of Big Bend National Park, the largest park in the state. Brewster County is bordered by Presidio County to the west, Jeff Davis County to the northwest, Pecos County and Terrell County to the east, and the Rio Grande to the south.
Alpine is a city in and the county seat of Brewster County, Texas, United States.  The population was 5,905 at the 2010 census.  The town has an elevation of 4,475 ft (1,364 m), and the surrounding mountain peaks are over a mile (1600 m) above sea level. The university, hospital, library, and retail make Alpine the center of the sprawling 12,000 square miles (31,000 km2) but wide open Big Bend area (combined population only 12,500) including Brewster, Presidio, and Jeff Davis Counties.
The town sits on a high plateau, in the Chihuahua Desert, with the Davis Mountains to the north and the Chisos Mountains to the south. Outcrops of ancient volcanic rocks spread to the northwest. Other layers of rocks have been exposed over time as the mountains were forced up and then eroded. The high elevation cools the desert air in the evenings.