Los Alamos (, meaning The Cottonwoods) is a census-designated place in Los Alamos County, New Mexico, United States, that is recognized as one of the development and creation places of the atomic bomb—the primary objective of the Manhattan Project by Los Alamos National Laboratory during World War II. The town is located on four mesas of the Pajarito Plateau, and had a population of about 13,200 as of 2020. It is the county seat and one of two population centers in the county known as census-designated places (CDPs); the other is White Rock.
Toponym
Los Alamos is a Spanish place name that typically refers to poplar or cottonwood trees. Alternatively, Los Alamos could refer to the large groves of aspen trees () that intersperse the coniferous forest on the mountainsides above the townsite, where they are distinctly visible during the autumn months due to their spectacular autumn colors.
History
The ruins of permanent Puebloan settlements, such as those located in nearby Bandelier National Monument and Tsankawi, and numerous other sites such as cliff dwellings indicate that the area has been inhabited during various eras since around 1150 AD. The first settlers on the plateau are thought to be Keres speaking Native Americans around the 10th century. Around 1300, Tewa settlers immigrated from the Four Corners Region and built large cities but were driven out within 50 years by Navajo and Apache raids and by drought.
In the late 19th century, homesteaders utilized the land for ranching. Most homesteaders built simple log cabins that they only lived in during warm weather to feed livestock. Many of the homesteaders later moved down to the warmer Rio Grande Valley. In 1917, homesteader Harold H. Brook sold part of his land and buildings to Ashley Pond II, a businessman from Detroit who founded the Los Alamos Ranch School. The area was used to teach young men basic ranching and other outdoor survival skills.
In 1943, during World War II, the United States Department of War exercised eminent domain over the Ranch School and all remaining homesteads in the area so that the relatively isolated location could be used for the secretive Manhattan Project, which ultimately developed the world's first nuclear weapons. Facilities for research and development were quickly built and scientists and engineers from all over the world were assigned to the project; however, all information about the town and project was held secret from the public. Los Alamos was referred to under the code name "Site Y" by military personnel, and was known only as "The Hill" by many in nearby Santa Fe.
Los Alamos was originally built as a closed city accessible from the outside world through only two gates. The specific location of the project was a tightly guarded secret. All employees recruited to work at the Los Alamos site were given a memorandum instructing them to travel to Santa Fe and report to the U.S. Army Corps of Engineers office at 109 East Palace Avenue. At that location, Dorothy McKibbin provided newcomers with the necessary documentation to get through security checkpoints (initially, letters signed by J. Robert Oppenheimer himself, and later, security passes), along with specific directions to the Hill. The project was further concealed by designating its mailing address as PO Box 1663, Santa Fe, N.M. All incoming truckloads were falsely labeled as common items in order to conceal the true nature of their contents, and any outbound correspondence by those working and living in Los Alamos was censored by military officials.
Not until after the bombing of Hiroshima was information about the Manhattan Project released to the public; being announced by the White House at 11 am on 6 August (when Nichols was able to tell his wife what he had been doing). A set of press releases were given out over three days.
In the years after World War II, the laboratory was formally established as a research government facility under the civilian control of the U.S. Atomic Energy Commission, and is now known as Los Alamos National Laboratory. In 1957, the AEC pulled back the security perimeter to the laboratory itself and opened up the town for visits by the general public. The first visitor to enter the town that year without a permit from the federal government was New Mexico Governor Edwin L. Mechem. The AEC was later succeeded by the U.S. Department of Energy.
Geography
Los Alamos is located in northern New Mexico between the Rio Grande and the eastern rim of the Valles Caldera on the Pajarito Plateau, approximately to the northwest of Santa Fe. The elevation at the post office is and total land area is .