Waters and hydrographic features

Cache Creek Ocean

Cache Creek Ocean: ancient Panthalassa ocean basin preserved as the exotic Cache Creek terrane of British Columbia and Yukon, with Tethyan Permian fusuline fossils, blueschist, and Jurassic closure during Intermontane terrane amalgamation.

Cachuma Lake

Lake Cachuma is a Santa Ynez River reservoir in Santa Barbara County, California, formed by Bradbury Dam (Cachuma Project, 1950-1956). It supplies South Coast drinking water and hosts a county recreation area with camping, fishing, and boating.

Caldas Novas

Caldas Novas is a municipality in southern Goiás, Brazil, sitting over one of the world's largest non-volcanic thermal groundwater systems and drawing hundreds of thousands of tourists.

California Boulder Patch

California Boulder Patch (variant California Boulder) is a named bar or rock group in Wrangell Narrows on the west coast of Mitkof Island, 12 miles south of Petersburg, Alaska, named in 1881 by Lt. Cmdr. H.E. Nichols, USN, presumably for the steamer California.

California Current

The California Current is a cold, equatorward eastern boundary current of the North Pacific gyre along the US West Coast, spanning nearly 3,000 km from British Columbia to Baja California; wind-driven seasonal upwelling fuels one of the world's most productive marine ecosystems.

Calistoga, California

Calistoga is a small city at the northern end of Napa Valley, California, founded by Sam Brannan in 1859 and incorporated in 1886. Known for hot springs, mud baths, the Calistoga AVA wine region, and its hydrogen-battery emergency power system.

Caloosahatchee River

The Caloosahatchee River (C-43 canal) is a eutrophic southwest Florida waterway flowing from Lake Okeechobee to the Gulf of Mexico, dredged from 1881 and channelized in the 1920s, plagued by cyanobacterial harmful algal blooms and managed through the C-43 West Basin Storage Reservoir.

Camargue

Camargue: the Rhône River delta in southern France, France's largest wetland (150,000 ha). Flat, mostly below 1 m elevation; rice, salt, bulls, flamingos; Ramsar and biosphere protected, threatened by sea-level rise.

Campbell Plateau

Campbell Plateau, large submarine continental platform of Zealandia extending southeast from Stewart Island, New Zealand; adjacent to Marie Byrd Land before Late Cretaceous, separated by Pacific-Antarctic spreading at 83-79 Ma.

Canada Basin

Canada Basin is the largest, deepest, and oldest part of the Arctic Ocean's Amerasia Basin, about 1,000,000 km² between 110°–160°W and 70°–85°N, formed by Cretaceous seafloor spreading and hosting the Beaufort Gyre freshwater reservoir.

Canal bend

Canal bend (GeoNames code CNLB): a conspicuously curved or bent section of a canal, a gazetteer hydrographic feature; in engineering called a canal curve, designed with minimum radii to limit inner-bend silting and outer-bank scour.

Canal do Norte

Canal do Norte (North Channel) is the northern approach channel of the Amazon River estuary in Amapá, Brazil, leading 75 miles to Macapá; also the name of channels at Maputo, Mozambique, and Rio Grande do Sul.

Canal do Sul

Canal do Sul (Southern Channel), marine channel in Pará, Brazil; entrance channel of the southern arm of the Amazon River north of Ilha do Marajó, least charted depth 5.8 m, max recommended draft 8.2 m; also a namesake channel in Recife, Pernambuco.

Canal Perigoso

Canal Perigoso (Dangerous Channel) is a shallow marine channel in Amapá, Brazil, separating Caviana and Mexiana islands in the Amazon estuary; hazardous to navigate, it links the Canal Norte and Canal Sul.

Canalized stream

Canalized (channelized) stream: a stream engineered by straightening, widening, deepening, or relocating its channel for flood control, drainage, or navigation; over 200,000 miles of US waterways were modified by 1970, with reduced habitat and faster flow.

Canary Basin

The Canary Basin is the region of the eastern North Atlantic off northwest Africa, dominated by the southward Canary Current and monitored for the Atlantic Meridional Overturning Circulation.

Caniapiscau

Caniapiscau names a ~400 km river in northern Quebec flowing to Ungava Bay via the Koksoak, and the large reservoir (impounded 1981) that diverts 40% of its flow to Hydro-Québec's La Grande complex.

Caño Cristales

Caño Cristales, the "River of Five Colors" or "liquid rainbow," is a river in La Macarena, Meta, Colombia, within Sierra de la Macarena National Park; the endemic aquatic plant Macarenia clavigera turns its bed red, yellow, green, blue, and black each mid-year season.

Cantabric Coast - Languedoc

Cantabric Coast - Languedoc (FEOW ecoregion 403) is a temperate coastal rivers freshwater ecoregion from Galicia to the French Mediterranean coast, spanning the Garonne-Adour-Dordogne and lower Rhône drainages, with about a dozen endemic fish and the Camargue, Western Europe's largest delta.

Cape Basin

Cape Basin: deep southeast Atlantic ocean basin off southwestern Africa, bounded by the Agulhas and Walvis ridges; opened 126-123 Ma, site of Agulhas leakage, the Cape Cauldron eddy regime, and Benguela upwelling sediments.

Cape Cod Canal

The Cape Cod Canal is a 17.4-mile sea-level waterway in Massachusetts, opened as a private toll canal in 1914 and now run by the US Army Corps of Engineers; the world's widest sea-level canal, crossed by the aging Bourne and Sagamore bridges being replaced.

Cape Fold

The Cape Fold is a freshwater ecoregion at South Africa's southern tip, whose coastal rivers hold the highest concentration of threatened freshwater fish in southern Africa.

Cape Verde

Cape Verde (Cabo Verde), ten-island Atlantic archipelago 500 km off West Africa, independent from Portugal since 1975; upper-middle-income since 2025 with a tourism-driven economy, euro-pegged escudo, and Sal and Boa Vista as main tourist islands.

Cape Wallace

Cape Wallace, a cape at the north-western end of Low Island, South Shetland Islands, Antarctica (about 63°13'S 62°12'W). Main ice-free exposure on Low Island, type area of the Cape Wallace Beds with Late Jurassic marine fossils.

Caribbean Sea

The Caribbean Sea is a tropical sea of the North Atlantic Ocean, also called the American Mediterranean Sea with the Gulf of Mexico, bounded by Central and South America and the West Indies, with coral reefs and the Caribbean Through-Flow feeding the AMOC.

Carnegie

Carnegie: chiefly Lake Carnegie, a 5,700 km2 ephemeral saline lake in the Shire of Wiluna, Western Australia, filling episodically after cyclones; Martu heritage site and 2023 nature reserve.

Caroní

Caroni River (Rio Caroni), major blackwater Orinoco tributary in Bolivar state, Venezuela, about 840 km long; its Guri, Macagua, Caruachi and Tocoma dams supply most of Venezuela's hydroelectric power. Distinct from Trinidad's Caroni River.

Caryapundy Swamp

Caryapundy Swamp, Ramsar Site no. 2520, is a 70,176-hectare ephemeral wetland in Narriearra Caryapundy Swamp National Park, NSW, Australia, the terminal basin of the endorheic Bulloo River, listed 17 December 2021 for threatened species and waterbird habitat.

Cascadia Basin

Cascadia Basin (Cascadia Abyssal Plain, Great Trough) is a ~170,000 km² sediment-filled deep-sea basin in the NE Pacific on the Juan de Fuca plate, bounded by the Juan de Fuca Ridge, Blanco fracture zone, and the Cascadia subduction zone.