Barker Dam, also known as Big Horn Dam, is a dam with water-storage reservoir located in Joshua Tree National Park in California. The dam was constructed by early cattlemen, including C. O. Barker, in 1900. It was raised in 1949 by rancher William F. Keys. It is situated between Queen Valley and the Wonderland of Rocks near the Wall Street Mill. It is a …Barker Dam, also known as Big Horn Dam, is a dam with water-storage reservoir located in Joshua Tree National Park in California. The dam was constructed by early cattlemen, including C. O. Barker, in 1900. It was raised in 1949 by rancher William F. Keys. It is situated between Queen Valley and the Wonderland of Rocks near the Wall Street Mill. It is a gathering place for desert wildlife, including many species of birds and desert bighorn sheep. Visitors can reach the dam via a short loop trail from a nearby parking lot off Barker Dam Road, and can see Native American petroglyphs a short distance to the west. There is also good bouldering on side trails near the dam. The park offers a Barker Dam Nature Hike led by a ranger.