Region
United States
173
California
9
West (U.S.)
9
Montana
7
Arizona
6
Manhattan Project National Historical Park
6
New York (State)
6
Colorado
5
Florida
4
New Mexico
4
Sagamore Hill National Historic Site (Oyster Bay, N.Y.)
4
Idaho
3
Montezuma National Wildlife Refuge (N.Y.)
3
New York
3
Oregon
3
Rocky Mountain Arsenal National Wildlife Refuge (Colo.)
3
Utah
3
Virginia
3
Washington (D.C.)
3
Washington (State)
3
Alaska
2
Cape Lookout National Seashore (N.C.)
2
Death Valley National Park (Calif. and Nev.)
2
Don Edwards San Francisco Bay National Wildlife Refuge
2
Don Edwards San Francisco Bay National Wildlife Refuge (Calif.)
2
Glacier National Park
2
Grant-Kohrs Ranch National Historic Site (Mont.)
2
Great Falls Park (Va.)
2
Hanford
2
Herbert Hoover National Historic Site (West Branch, Iowa)
2
Los Alamos (N.M.)
2
Morris County
2
Morristown National Historical Park (N.J.)
2
National Park of American Samoa (American Samoa)
2
Nevada
2
New Jersey
2
North America
2
North Carolina
2
Oak Ridge (Tenn.)
2
Oregon National Historic Trail
2
Outer space
2
Oyster Bay
2
Portsmouth (N.C.)
2
President's Park (Washington, D.C.)
2
Statue of Liberty National Monument (N.Y. and N.J.)
2
Sun
2
Theodore Roosevelt Birthplace National Historic Site (New York, N.Y.)
2
Abraham Lincoln Birthplace National Historical Park
1
Abraham Lincoln Birthplace National Historical Park (Ky.)
1
Agua Fria National Monument
1
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