Region
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Black Hills National Forest (S.D. and Wyo.)
5
Blue Mountains (Or. and Wash.)
5
Boston
5
Chesapeake Bay (Md. and Va.)
5
Effigy Mounds National Monument
5
Effigy Mounds National Monument (Iowa)
5
Everglades
5
Interior Alaska
5
Kenya
5
Klamath National Forest (Calif. and Or.)
5
Mall, The (Washington, D.C.)
5
Mississippi
5
Nile River Watershed
5
Ontario
5
Philippines
5
Russia
5
Sonoran Desert National Monument
5
South Dakota
5
Stones River National Battlefield (Tenn.)
5
White River National Forest
5
White River National Forest (Colo.)
5
Africa, Eastern
4
American Samoa
4
Apalachicola River Watershed
4
Apostle Islands National Lakeshore (Wis.)
4
Argentina
4
Arlington
4
Aurora
4
Baltimore
4
Billings County
4
Billings County (N.D.)
4
British Columbia
4
Cambodia
4
Congo (Democratic Republic)
4
Connecticut
4
Egypt
4
Fossil Creek
4
Fossil Creek (Ariz.)
4
Fredericksburg and Spotsylvania National Military Park (Va.)
4
Glen Canyon National Recreation Area (Utah and Ariz.)
4
Golden
4
Great Plains
4
Guam
4
Las Vegas
4
Mediterranean Region
4
Morley Nelson Snake River Birds of Prey National Conservation Area (Idaho)
4
National Petroleum Reserve
4
New England
4
New York Metropolitan Area
4
Pacific Coast (North America)
4
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