Region
Arizona
22
Colorado
20
Alaska
19
Nevada
17
Montana
16
United States
16
California
13
Utah
13
Wyoming
13
Middle West
12
North America
11
Maine
10
New Mexico
10
Virginia
10
West (U.S.)
9
Appalachian Region
7
Texas
7
Idaho
6
Appalachian Mountains
5
Florida
5
Kansas
5
Massachusetts
5
Mississippi
5
New England
5
Sierra Nevada (Calif. and Nev.)
5
Arkansas
4
Cochise County
4
Connecticut
4
Georgia
4
Inyo County
4
Missouri
4
Oquirrh Mountains
4
Antarctica
3
Appalachian Basin
3
Aroostook County
3
Colorado River Watershed (Colo.-Mexico)
3
Death Valley (Calif. and Nev.)
3
Grand Canyon
3
Grand Canyon (Ariz.)
3
Great Basin
3
Illinois
3
Illinois Basin
3
Moose River
3
Navajo Indian Reservation
3
New Hampshire
3
New Jersey
3
Nye County
3
Oklahoma
3
Anadarko Basin
2
Black Pine Mountains
2
more ...