Big Bend National Park is a national park located in Texas. For more than 1,000 miles (1600 km) the Rio Grande / Río Bravo forms the international boundary between Mexico and the United States; Big Bend National Park administers approximately one-quarter of that boundary. It has national significance as the largest protected area of Chihuahuan Desert topography and ecology in the United States. The park covers 1252 mi² (3242 km²). Few areas exceed the park's value for the protection and study of geologic and paleontologic resources. Cretaceous and Tertiary fossil organisms exist in variety and abundance. Archeologists have discovered artifacts estimated to be 9,000 years old, historic buildings and landscapes offer graphic illustration of life along the international border at the turn of the century.
Because the Rio Grande serves as an international boundary the park faces unusual constraints when administering and enforcing park rules, regulations, and policies. The park has jurisdiction only to the center of the deepest river channel; the rest of the river lies within Mexican territory.