in Yukon River at mouth of Fourth of July Creek, 34 mi. NNW of Eagle, Yukon-Tanana High.
Local name published in 1956 by U.S. Geological Survey (USGS). The generic "reef" may refer to rock stratum that extends into or across the Yukon River at this point and may be the same stratum that J. B. Mertie, Jr., U.S. Geological Survey (USGS), called "Rock of Ages" in 1937.
Bull Creek, Butte Creek, Crowley Creek, Dewey Creek, Fourth of July Creek, Gillman Creek, Hard Luck Creek, Logan Creek, Michigan Creek, Ruby Creek, Schley Creek, Trout Creek, Tyrena Creek,
Valleys:Eight Gulch, Independence Gulch, Lucky Gulch, Owl Gulch, Seven Gulch, Seventeen Gulch, Ten Gulch, Thirteen Gulch, U.S. Gulch, Union Gulch,