Columbia subject headings:
Harvard subject headings:
Lewis and Clark National Historical Park (Or. and Wash.)--History.
Lewis and Clark National and State Historical Parks (Or. and Wash.)--History.
Lower Columbia River Valley (Or. and Wash.)--History.
Princeton subject headings:
Lewis and Clark National Historical Park (Or. and Wash.)--History.
Lewis and Clark National and State Historical Parks (Or. and Wash.)--History.
Lower Columbia River Valley (Or. and Wash.)--History.