There are 18 National Natural Landmarks in the U.S. state of Washington, out of nearly 600 National Natural Landmarks in the United States.
Name Image Date Location County Ownership Description Boulder Park and McNeil Canyon Haystack Rocks Douglas Federal, state The most illustrative examples of glacial erratics in the United States. Davis Canyon Okanogan State, private One of the largest and least disturbed examples of antelope bitterbrush-Idaho fescue shrub steppe remaining in the Columbia Plateau. Drumheller Channels Adams, Grant Federal, state, private Illustrates the dramatic modification of the Columbia Plateau volcanic terrain by late Pleistocene catastrophic glacial outburst floods. Includes Columbia National Wildlife Refuge. Ginkgo Petrified Forest Kittitas State Thousands of logs petrified in lava flows. Part of Ginkgo/Wanapum State Park. Grand Coulee Grant Federal, state, private An illustration of a series of geological events. Grande Ronde Feeder Dikes Asotin Private The best example of basalt dikes, the congealed feeder sources of the Columbia River basalt plateau. Grande Ronde Goosenecks Asotin Federal A deep canyon that follows a tortuous path along meanders. The Great Gravel Bar of Moses Coulee Douglas State, private Largest and best example of a pendent river bar formed by catastrophic glacial outburst floods that swept across the Columbia Plateau. Kahlotus Ridgetop Franklin State The best remaining example of the Central Palouse Prairie grassland subtheme. Mima Mounds Thurston State A prairie containing unusual soil pimples of black silt-gravel. Nisqually Delta Pierce, Thurston Federal, state, tribal, private An unusually fine example of an estuarine ecosystem. Includes Nisqually National Wildlife Refuge. Point of Arches Clallam Federal An outstanding exhibit of sea action in sculpturing a rocky shoreline. A unit of Olympic National Park. Rose Creek Preserve Whitman Private The best remaining example of the aspen phase of the hawthorne-cow parsnip habitat type in the Columbia Plateau. Managed by The Nature Conservancy. Sims Corner Eskers and Kames Douglas Federal, state, private The best examples in the Columbia Plateau of landforms resulting from stagnation and rapid retreat of the ice sheet during the last glaciation. Steptoe and Kamiak Buttes Whitman State, county, private Isolated mountain peaks of older rock surrounded by basalt, rising above the surrounding lava plateau. Umtanum Ridge Water Gap Kittitas Federal, state, private Geologic formation that illustrates the processes of tectonic folding and antecedent stream cutting. Wallula Gap Benton, Walla Walla Federal, state, county, municipal The largest and most spectacular of several large water gaps through basalt anticlines in the Columbia River basin. Withrow Moraine and Jameson Lake Drumlin Field Douglas Federal, private The best examples of drumlins and the most illustrative segment of the only Pleistocene terminal moraine in the Columbia Plateau
See also
List of National Historic Landmarks in Washington
References General
Footnotes