This is a List of National Historic Landmarks in Arizona. There are 47 National Historic Landmarks (NHLs) in Arizona, counting Hoover Dam that spans from Nevada and is listed in Nevada by the National Park Service (NPS), and Yuma Crossing and Associated Sites, which is listed by the NPS in Arizona, and overlaps into California. The first designated was San Xavier del Bac Mission, in October, 1960. The most recently designated is the Klagetoh (Leegito) Chapter House in January 2021.