Hueco Tanks is an area of low mountains and historic site in El Paso County, Texas, in the United States. It is located in a high-altitude desert basin between the Franklin Mountains to the west and the Hueco Mountains to the east. "Hueco" is a Spanish word meaning "hollows" and refers to the many water-holding depressions in the boulders and rock faces throughout the region. Due to the unique concentration of historic artifacts, plants and wildlife, the site is under protection of Texas law; it is a crime to remove, alter, or destroy them.