Region
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Andes Region
2
Andhra Pradesh
1
Angaur Island
1
Angola
2
Animas River (Colo. and N.M.)
2
Animas River Watershed
2
Animas River Watershed (Colo. and N.M.)
6
Anniston
6
Anniston (Ala.)
2
Anoka County
1
Antarctica
11
Antelope Valley
1
Apache-Sitgreaves National Forest
1
Apalachicola National Forest
1
Apalachicola River (Fla.)
1
Appalachian Basin
1
Appalachian Region
38
Appalachian Region, Southern
6
Arabian Peninsula
1
Arapahoe County
1
Arctic Coast
2
Arctic National Wildlife Refuge
20
Arctic National Wildlife Refuge (Alaska)
12
Arctic Ocean
5
Arctic regions
18
Argentina
5
Arizona
68
Arkansas
5
Arkansas City
1
Arkansas River
1
Arkansas River Valley
1
Arkansas River Watershed
1
Arlit
2
Arlit (Niger)
2
Armstrong County
1
Arnold Air Force Base Region
1
Arrowrock Reservoir
1
Arrowrock Reservoir (Idaho)
1
Arthur Kill (N.J. and N.Y)
2
Arthur Kill (N.J. and N.Y.)
3
Ashland
1
Ashland Region
2
Ashton/Island Park Ranger District (Idaho)
2
Ashumet Valley
1
Asia
27
Asia, Central
2
Aspen
1
Aspen (Colo.)
1
Asturias
1
Asturias (Spain)
1
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