The park encompasses a 40 mile section between Chatham and Provincetown and includes numerous historic structures, most notably five lighthouses and lifesaving stations, and the Penniman and Atwood-Higgins Houses. The museum collection includes archeological objects (with associated field records) systematically recovered from prehistoric sites within the park's boundaries; natural history specimens and associated field records; historic objects and archival materials relating to lighthouses, cranberry production, and the fishing industry; and scrimshaw. Historic furnishings are on display in the Atwood-Higgins House (c. 18th century) and the Penniman House (c. 19th century).

The collections are particularly strong in the areas of archeology and archival materials. Holdings include: