The United States took possession of Wake Island in 1899. One of 14 U.S. insular areas, Wake Island is administered by the United States Air Force under an agreement with the U.S. Department of the Interior. The center of activity on the atoll is at Wake Island Airfield, which is primarily used as a mid-Pacific refueling stop for military aircraft and as an emergency landing area. The runway is the longest strategic runway in the Pacific islands. South of the runway is the Wake Island Launch Center, a missile launch site. The island has no permanent inhabitants, and approximately 100 people live there at any given time.