The McDonald Ranch House
The house was built in 1913 by Franz Schmidt, a German immigrant. An addition on the north side was built in the 1930s by the Mcdonald family, the last owners before the federal government leased the land in 1942 and purchased it in 1983. The 1,750 square foot home is built of adobe plastered with stucco. 
The McDonald House was appropriated by the federal government to serve as the assembly area for Trinity. 
The remains of Dave McDonald’s ranch house. 
The corrals and stables at Dave McDonald’s ranch prior to the area being tagged for the Trinity Test. 
The Schmidt ranch was a working ranch with over 12,000 sheep and 1,000 cattle. The sheep were divided into six herds, each with a herder and a dog. 
The remains of the Schmidt/Mcdonald ranch bunkhouse, barn/garage, and corrals. 
The explosion, two miles away, blew out the windows but did not damage the house. It stood empty and deteriorated until WSMR stabilized it in 1982 and worked with the Department of Energy and the National Park Service to restore it in 1984 to how it appeared in July 1945. 
Francis Schmidt, the oldest daughter of Franz Schmidt, lived at the ranch prior to when the McDonalds moved in. Francis corresponded with WSMR in her later years, providing descriptions of the ranch house that proved valuable in its restoration.
Prior to World War II, Trinity was the site of ranches owned by the McDonald brothers who moved in during the 1920s. Despite protests, they were one of several families forced to leave their ranches in early 1942 when the land was leased to establish the Alamogordo Bombing Range to train WWII crews. Dave McDonald’s ranch served as the base camp; George McDonald’s ranch house was the location where the Trinity team assembled the bomb’s plutonium core. Disputes over compensation for the land, its facilities, cattle, and potential earnings continue to this day.
The ranch site was originally built in 1913 by Franz Schmidt, a German who immigrated to the United States in 1863 at age 17. He worked for merchants in New York City, was reassigned to Santa Fe, New Mexico, and in 1906 married Esther Holmes, an 18-year old Texas farm girl. After giving up on the mercantile business, he became a rancher in the Tularosa Basin. Records show Baldy Russell from Engle, New Mexico sold two ranches to Franz and Fred Schmidt. Fred ran the second ranch just west of Mockingbird Gap. Franz’s first house burned down, built a new one about a mile away, known today as the Schmidt-McDonald Ranch House, which was where the plutonium core to the first atomic bomb was assembled.
The bomb’s explosion, two miles away, blew out the windows of the ranch house, but did not damage the house itself. Although the ranch house was largely undamaged, the blast took off part of the barn roof which eventually collapsed. The house stood empty and deteriorating until WSMR stabilized it in 1982. In 1984, WSMR partnered with the Department of Energy and the National Park Service to restore it to how it appeared, including any deteriorated stucco, in July 1945.