Although the majority of prehistoric habitation sites on Santa Cruz Island are located within interior areas more than 0.5 km from the coast, little is known about these sites and how their occupation articulated with coastal settlement. To address this lack of knowledge, small-scale excavation was undertaken at 2 interior habitation sites (CA-SCRI-555 and CA-SCRI-574) in the western sector of the island. Habitation deposits at both sites are <60 cm deep. Radiocarbon dating reveals that CA-SCRI-555 experienced occupation during 3 time intervals: 1800–1400 cal BC, ~2400 cal BC, and ~4400 cal BC. In contrast, dates for CA-SCRI-574 indicate only one time interval: 2800–1900 cal BC. Remains of marine shellfish and vertebrates in the deposits indicate transport of marine foods to both sites. The repertoire of shellfish remains implies that site inhabitants obtained marine foods from coastal areas closest to each site. These interior sites may have been occupied for one or more reasons: (1) as habitation sites occupied occasionally for the purpose of acquiring and perhaps consuming plant food or other interior resources; (2) as easily defended locations given their placement on ridgetops; (3) as way stations during travel to distant parts of the island; and (4) as locations where freshwater is available during dry seasons or years when water is scare at nearby coastal locations. The data resulting from small-scale testing makes evaluating these alternatives difficult, but the variety of food remains, the various types of stone tools, and the wood charcoal from hearth fires all indicate that at least some intervals of occupation were for periods that exceeded a few days. The results highlight the need for data from a large number of interior sites to understand island settlement patterns and ecological adaptation of the island's prehistoric inhabitants.