Region
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Front Range Region (Colo. and Wyo.)
1
Galapagos Islands
2
Grant County
1
Great Basin
3
Great Lakes (North America)
11
Great Lakes Region (North America)
1
Great Plains
1
Guanacaste National Park
1
Guanacaste National Park (Costa Rica)
1
Gulf Coast (U.S.)
18
Gulf States
8
Gulf of Mexico
1
Hawaii
1
Hudson River (N.Y. and N.J.)
1
Humboldt-Toiyabe National Forest (Nev. and Calif.)
1
Iceland
1
Illinois
8
Illinois Waterway
7
Illinois Waterway (Ill.)
3
Indiana Dunes National Park (Ind.)
1
Inland Empire
1
Iowa
3
Islands of the Pacific
1
Jefferson Parish
1
Jefferson Parish (La.)
1
Los Angeles River
1
Los Angeles River (Calif.)
1
Louisiana
13
Lynnhaven River Watershed
1
Lynnhaven River Watershed (Va.)
1
Manchuria
2
Mancos Shale
1
Mediterranean Region
1
Mekong River Watershed
2
Mexican-American Border Region
3
Mexico, Gulf of
11
Miami-Dade County
1
Middle Atlantic States
1
Middle West
6
Mississippi River Valey
1
Mississippi River Valley
9
Mississippi Sound
1
Missouri River
3
Missouri River Watershed
3
Mongolia
2
Montana
3
Murfree Spring (Murfreesboro, Tenn.)
1
Murfreesboro
1
Neuse River Watershed
1
Neuse River Watershed (N.C.)
1
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