Located in south-central Oregon along the shores of Gerber Reservoir, the Peninsula Site, 35KL87, was test excavated during the summer of 1986 by the University of Oregon Archaeological Field School. Circular rock features observed at the site were found to be habitation structures. Radiocarbon dates and typological comparisons with other sites in the region suggest that the site's occupational history spans the last 4,000 to 5,000 years ago.
The evidence of artifacts and cultural features as well as the biotic setting of the site indicates plant and animal food processing took place at the site and a high degree of sedentism was characteristic of the prehistoric inhabitants. The presence of tools that apparently were used in the manufacture of mortars and metates is an apparently unique feature of the site. Rock art of Great Basin Curvilinear Abstract Style cooccurs with grinding features. This is suggestive of an association between the rock art and its motifs and the activities of women.
Present evidence suggests that the site was both a winter and summer village between 4,000 and 1,000 B.P. and that sometime between 2,000 and 1,000 B.P. use as a summer village intensified. Occupation appears to have continued to just before historic contact, although use during the winter may have decreased in later years. This intensification of summer use and possible decrease in winter use are seen as related to environmental change, an increased dependence on upland resources, an increased local population, a possible movement of a displaced ancestral Klamath-Modoc population into the area, and a shift in the site's role within a broader geographic-cultural interaction zone as Penutian speaking peoples abandoned the northwestern Great Basin and its greatly diminished lake-marsh ecosystems. Recommendations are given for testing this and two alternate hypotheses.