Riddle Ranch, Pioneer ranch complex in Harney County, Oregon, United States

Riddle Ranch is a ranch complex of eight historical buildings constructed from logs, weatherboard, hand-cut shingles, and stone situated along the Little Blitzen River. The site preserves the original arrangement of residential buildings, barns, and working structures needed for daily cattle ranching operations.

The Riddle family's Happy Valley ranch was burned in 1878 during the Native American wars; Peter French of the P Ranch bought the property for $30,000. Around 1900 Benjamin, Fred, Walter, Carrie and uncle George Riddle returned, took over Scott Catterson's squatter's claim, and raised mules and horses for the military. After mechanization following World War I they switched to cattle, expanding to 1,120 acres and controlling all local water. Fred, the last brother, sold to Rex Clemens in 1952; the BLM bought the site in 1986 and listed it in 1991.

The ranch is named for the Riddle family, whose third generation settled here around 1900. Fred and Walter Riddle ran it for about fifty years; neither brother ever married. The site is now an open-air museum with original artifacts displayed where they were used, and Native American archaeological sites on the property are not open to the public.

The ranch sits on both banks of the Little Blitzen River on public land in the Steens Mountain Cooperative Management and Protection Area, reached by unpaved roads in Harney County. Camping is not permitted on the property. Visitors can walk among the buildings, hike, and fish; the Native American archaeological sites on the ranch are closed to the public.

The site shows a rare example of water management on an early American ranch, with visible canals and irrigated fields that remain traceable today. This infrastructure was essential for the ranch to thrive in a dry mountain region.