Region
Great Plains
United States
484
West (U.S.)
272
Grandes Plaines
170
North America
158
South Dakota
87
West United States
85
Middle West
78
Montana
74
United States, West
66
Nebraska
63
North Dakota
63
Kansas
56
Rocky Mountains
49
Canada
42
Wyoming
42
Rocky Mountains Region
40
Southwest, New
37
Oklahoma
35
Prairie Provinces
34
Texas
32
Mississippi River Valley
26
États-Unis
22
California
21
Colorado
21
Minnesota
21
New Southwest
19
Mississippi River
18
Missouri River Valley
18
Utah
17
Alberta
16
New Mexico
16
Ogallala Aquifer
16
Missouri River
15
High Plains Aquifer
14
Amérique du Nord
13
Dakota Territory
13
Northwest, Pacific
13
Southwestern States
13
Great Basin
12
Pine Ridge Indian Reservation (S.D.)
12
Saskatchewan
12
Southern States
12
High Plains (U.S.)
11
Mexico
11
Northwestern States
11
Plainsindianer
11
Amérique du Nord
10
Missouri
9
Nordamerika
9
more ...