Place
- Central Arizona Project Aqueduct1
- Central California Mountains1
- Central Corn Belt Plains1
- Central Great Plains1
- Central Irregular Plains1
- Central Oklahoma/Texas Plains1
- City of Douglas1
- Coast Range1
- Cochise Country1
- Colorado Plateaus1
- Colorado River1
- Columbia Plateau1
- Connecticut1
- Conterminous United States1
- Delaware1
- Douglas1
- Driftless Area1
- East Central Texas Plains1
- Eastern Cascades Slopes and Foothills1
- Eastern Corn Belt Plains1