Hell Gap (Smithsonian trinomial: 48GO305) is a deeply stratified archaeological site located in the Great Plains of eastern Wyoming, approximately thirteen miles north of Guernsey, where an abundant amount of Paleoindian and Archaic artifacts have been found and excavated since 1959. This site has had an important impact on North American archaeology because of the large quantity and breadth of prehistoric Paleoindian and Archaic period (ca. 13,500 to 7,600 B.P.) artifacts and cultures it encompasses. It was designated a National Historic Landmark in 2016.

Hell Gap contains projectile points from the Llano tradition, Clovis and Folsom, and the Plano tradition, Agate Basin, Alberta, Frederick, Goshen (Plainview), Lusk, Hell Gap, Midland, and Cody complexes.[6] Three new archaeological complexes were defined at this site, Hell Gap, Goshen (Plainview), and Frederick. Folsom complex is believed to be derived from Clovis but there has not been much radiocarbon-dated evidence in stratified context between the two assemblages to determine this for certain. The Goshen complex found in Hell Gap is a possible assemblage dating to this intermediate period. The Hell Gap and Agate Basin point forms, which were also found in stratified context at Hell Gap, are the first types of the Plano tradition. The earliest calibrated dates for Hell Gap and Agate Basin complexes are from 10,200 to 9,600 B.P.