The original log ranch structures in Sand Creek Canyon were designed in the rustic style by architect Ray Ewing.

Other buildings constructed at the time included a garage with an upstairs apartment, a barn, a hydroelectric power plant, stone entrance arches and a pump house.

He bought the 650-acre (260 ha) ranch from LaPlante on the spot the next day for $27,000 [today worth around $303,000 in 2010 dollars] in cash, which Annenberg produced from his pocket.

[3] The design work was done by South Dakota architect Ray Ewing, who hired the Juso Brothers to build the structures.

Work took place during the Great Depression, employing sixty to seventy workers, a significant project for the local economy.

[4] Annenberg came under Federal investigation for his business practices in the late 1930s and was convicted of income tax evasion in 1940, was imprisoned, and died shortly after his release in 1942.

In 1963 the Fish and Wildlife Service bought the ranch, using it as a genetics laboratory for salmonid research under the name "Spearfish Fisheries Center Complex."

The second story overhangs the first, creating a long veranda across the front of the building, supported by stone piers with standing log sections as columns.

The second story is a side gable dominated by shed dormers extending nearly the full width of the building, front and back.

The interior features an atrium extending to the roof, surrounded by living spaces on both levels, framed in log construction.

Other contributing structures include the pump house (1932), built in stucco with applied half-timber detailing and a rolled roof edge.