Region
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Blount County
1
Bootlegger Cove Formation
1
Bootlegger Cove Formation (Alaska)
1
Boston
1
Boston (Mass.)
1
Bradley County
1
Brazil
2
California
28
California, Southern
1
Callaway County
1
Campbell County
1
Canada
7
Canal Zone
1
Caribbean Area
2
Carroll County
1
Carter County
1
Cascade Range
1
Cassia County
1
Castle Creek, South Fork
1
Cattaraugus County
1
Cauca (Department)
2
Chambers County
1
Chapman Creek
1
Chapman Creek Region
1
Cheatham County
1
Chesapeake Bay Watershed
2
Chester County
1
Chihuahuan Desert
1
China
3
Chornobylʹ
1
Cincinnati Region
1
Claiborne County
1
Clark County
2
Clark County (Wash.)
1
Clark Fork (Mont. and Idaho)
2
Clark Fork Watershed (Mont. and Idaho)
1
Clear Creek County
1
Cocke County
1
Coconino County
1
Coffee County
1
Cold regions
2
Colombia
5
Colorado
11
Colorado Plateau
1
Colorado River
1
Colorado River (Colo.-Mexico)
1
Colorado Springs
1
Columbia River Valley
1
Columbus
1
Cone Pond Watershed
1
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