Question: The historic site that contains the ruins of a pueblo estimated to be 500 years old is in what Arizona county ?

text: List of National Historic Landmarks in Arizona
Current NHLs

This is a List of National Historic Landmarks in Arizona. There are 46 National Historic Landmarks (NHLs) in Arizona, counting Hoover Dam which 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, but also overlaps into California. The first designated was San Xavier del Bac Mission, in October, 1960. The most recently designated was the Painted Desert Community Complex Historic District in December 2016.
Landmark name Date designated Location County Description
1 1956 Grand Canyon TWA - United Airlines Aviation Accident Site April 23 , 2014 ( # 14000280 ) Grand Canyon National Park 36°10′30″N 111°49′59″W / 36.1750°N 111.833°W / 36.1750 ; -111.833 ( 1956 Grand Canyon TWA - United Airlines Aviation Accident Site ) Coconino Crash area of first major ( 100+ deaths ) commercial air disaster in the United States ; led to creation of Federal Aviation Administration
2 Air Force Facility Missile Site 8 ( Titan II ICBM Site 571-7 ) April 19 , 1994 ( # 92001234 ) Green Valley 31°54′05″N 110°59′54″W / 31.901339°N 110.998414°W / 31.901339 ; -110.998414 ( Air Force Facility Missile Site 8 ) Pima Last surviving Titan II missile launch facility ; inactive
3 Apache Pass and Fort Bowie December 19 , 1960 ( # 72000194 ) Bowie 32°08′46″N 109°26′08″W / 32.146111°N 109.435556°W / 32.146111 ; -109.435556 ( Apache Pass and Fort Bowie ) Cochise Commemorates the conflict between the Chiricahua Apaches and the United States military ; preserves the ruins of Fort Bowie
4 Awatovi Ruins July 19 , 1964 ( # 66000187 ) Keams Canyon 35°43′07″N 110°16′37″W / 35.718611°N 110.276944°W / 35.718611 ; -110.276944 ( Awatovi Ruins ) Navajo Ruins of a 500-year-old pueblo visited by Coronado 's men in
5 Casa Malpais Site July 19 , 1964 ( # 66000936 ) Springerville 34°09′N 109°18′W / 34.15°N 109.3°W / 34.15 ; -109.3 ( Casa Malpais Site ) Apache Ruin built around 1250 A.D. ; inhabited until about 1400 A.D by Mogollon culture . Tours and museum
6 Mary Jane Colter buildings May 28 , 1987 ( # 87001436 ) South Rim locations in Grand Canyon National Park 36°03′29″N 112°08′13″W / 36.058056°N 112.136944°W / 36.058056 ; -112.136944 ( Mary Jane Colter buildings ) Coconino Includes Desert View Watchtower , Hermits Rest , Hopi House , and The Lookout
7 Desert Laboratory December 21 , 1965 ( # 66000190 ) Tucson 32°13′31″N 111°00′09″W / 32.225278°N 111.0025°W / 32.225278 ; -111.0025 ( Desert Laboratory ) Pima Founded in 1903 to study plant adaptation to an arid desert environment with long term experiments , this laboratory contributed significantly to the formation of Ecology as a science . Part of the University of Arizona
8 Double Adobe Site January 20 , 1961 ( # 66000169 ) Douglas 31°21′00″N 109°32′00″W / 31.35°N 109.53333°W / 31.35 ; -109.53333 ( Double Adobe Site ) Cochise Archaeological site where development of the Cochise Culture occurred
9 El Tovar May 28 , 1987 ( # 74000334 ) Grand Canyon Village 36°03′21″N 112°08′13″W / 36.055704°N 112.136999°W / 36.055704 ; -112.136999 ( El Tovar ) Coconino Classic lodge at South Rim of Grand Canyon
10 Fort Apache and Theodore Roosevelt School March 2 , 2012 ( # 76000377 ) Fort Apache 33°47′23″N 109°59′21″W / 33.789812°N 109.98903°W / 33.789812 ; -109.98903 ( Fort Apache and Theodore Roosevelt School ) Navajo Site of historic Fort Apache ; later converted to a school for the purpose of assimilating the native population . It is now a tribal museum
11 Fort Huachuca May 11 , 1976 ( # 74000443 ) Sierra Vista 31°33′19″N 110°20′59″W / 31.555278°N 110.349722°W / 31.555278 ; -110.349722 ( Fort Huachuca ) Cochise Commemorates Buffalo Soldiers
12 Gatlin Site July 19 , 1964 ( # 66000183 ) Gila Bend 32°58′51″N 112°42′06″W / 32.980935°N 112.701612°W / 32.980935 ; -112.701612 ( Gatlin Site ) Maricopa Preserves a Hohokam platform mound , pit houses , ball courts , middens , and prehistoric canals
13 Grand Canyon Depot May 28 , 1987 ( # 74000337 ) Grand Canyon Village 36°03′15″N 112°08′11″W / 36.054295°N 112.136346°W / 36.054295 ; -112.136346 ( Grand Canyon Depot ) Coconino Railway station constructed in 1909-10 for the Atchison , Topeka and Santa Fe Railroad
14 Grand Canyon Lodge May 28 , 1987 ( # 82001721 ) North Rim , Grand Canyon National Park 36°11′57″N 112°03′07″W / 36.199167°N 112.051944°W / 36.199167 ; -112.051944 ( Grand Canyon Lodge ) Coconino Lodge at Bright Angel Point , on North Rim of Grand Canyon
15 Grand Canyon Park Operations Building May 28 , 1987 ( # 87001412 ) Grand Canyon Village 36°03′12″N 112°08′13″W / 36.053226°N 112.136908°W / 36.053226 ; -112.136908 ( Grand Canyon Park Operations Building ) Coconino National Park Service building ; built in 1929 ; designed to blend with the natural surroundings
16 Grand Canyon Power House May 28 , 1987 ( # 87001411 ) Grand Canyon Village 36°03′14″N 112°08′24″W / 36.053873°N 112.139970°W / 36.053873 ; -112.139970 ( Grand Canyon Power House ) Coconino Rustic building designed to conceal the purpose of the building , which was to provide power to the railroad
17 Grand Canyon Village February 18 , 1987 ( # 75000343 ) Grand Canyon Village 36°03′20″N 112°08′18″W / 36.055556°N 112.138333°W / 36.055556 ; -112.138333 ( Grand Canyon Village ) Coconino Planned town significant for its urban planning and ecological sensitivity
18 Hoover Dam August 20 , 1985 ( # 81000382 ) Lake Mead National Recreation Area 36°00′56″N 114°44′16″W / 36.015556°N 114.737778°W / 36.015556 ; -114.737778 ( Hoover Dam ) Mohave , AZ and Clark , NV Historic dam , power plant and water-storage facility
19 Hubbell Trading Post December 12 , 1960 ( # 66000167 ) Ganado 35°43′32″N 109°35′36″W / 35.725556°N 109.59333°W / 35.725556 ; -109.59333 ( Hubbell Trading Post ) Apache Meeting ground of two cultures , the Navajo and the settlers
20 Jerome Historic District November 13 , 1966 ( # 66000196 ) Jerome 34°45′13″N 112°06′41″W / 34.753611°N 112.111389°W / 34.753611 ; -112.111389 ( Jerome Historic District ) Yavapai Copper mining town