- Calaveras1
- Canadian Rockies1
- Cape Breton Island, Hazeldale, near Little Narrows1
- Carleton1
- Cascade Mountains, White River1
- Cebolla Creek Campground, between Cathedral and Slumgullion Pass1
- Cedar Brake adjacent to Hwy. 277, ca. 6 miles SW of View1
- Cedar Creek1
- Cedar Hill Cemetary, 2 miles NW Suitland1
- Central Pacific Coast District, Valdez Quadrangle, woods south of Valdez1
- Chancellor's Road, St. Ann's1
- Charlevoix1
- Cheboygan1
- Chestervale, below Cinchona1
- Chimborazo1
- Chipewyan1
- Cinchona1
- Citrus1
- City of Niagara Falls, near 99th St. School, cap over chemical dump of Love Canal1
- Clark1