The Kelso Site, near Mullen in Hooker County, Nebraska, United States, was listed on the National Register of Historic Places in 1974.
According to Nebraska History: "Kelso is located on a sand dune overlooking the Middle Loup River near the town of Mullen.
It is important as a rare example of a little known Woodland culture of the Sand Hills, Panhandle, and eastern Colorado dating A.D.
"[2] The archeological site was partially excavated in 1947, when the proposed Mullen Reservoir project was planned.
Artifacts included pottery, stone tools, animal remains, and a bone awl.