The story of Los Alamos and the Pajarito Plateau begins with explosive eruptions. An ancient volcano in northern New Mexico created the mountainous region known as the Jemez, and with time, erosion sculpted narrow mesas and canyons. The first residents were Native Americans. One of their many pueblos was called Tsirege, or the "bird place," from which the name Pajarito originates, meaning "little bird" in Spanish. Homesteaders arrived in the 1880s,...