Terlingua is a mining district and census-designated place in southwestern Brewster County, Texas, United States. It is located near the Rio Grande and the villages of Lajitas and Study Butte, Texas, as well as the Mexican state of Chihuahua. The discovery of cinnabar, from which the metal mercury is extracted, in the mid-1880s brought miners to the area, creating a city of 2,000 people.