| Country | Geography - note |
| Chad | landlocked; Lake Chad is the most significant water body in the Sahel |
| Chile | strategic location relative to sea lanes between Atlantic and Pacific Oceans (Strait of Magellan, Beagle Channel, Drake Passage); Atacama Desert is one of world's driest regions |
| China | world's fourth largest country (after Russia, Canada, and US); Mount Everest on the border with Nepal is the world's tallest peak |
| Christmas Island | located along major sea lanes of Indian Ocean |
| Clipperton Island | reef 12 km in circumference |
| Cocos (Keeling) Islands | islands are thickly covered with coconut palms and other vegetation; site of a World War I naval battle in November 1914 between the Australian light cruiser HMAS Sydney and the German raider SMS Emden; after being heavily damaged in the engagement, the Emden was beached by her captain on North Keeling Island |
| Colombia | only South American country with coastlines on both the North Pacific Ocean and Caribbean Sea |
| Comoros | important location at northern end of Mozambique Channel |
| Congo, Democratic Republic of the | straddles equator; has narrow strip of land that controls the lower Congo River and is only outlet to South Atlantic Ocean; dense tropical rain forest in central river basin and eastern highlands |
| Congo, Republic of the | about 70% of the population lives in Brazzaville, Pointe-Noire, or along the railroad between them |
| Cook Islands | the northern Cook Islands are seven low-lying, sparsely populated, coral atolls; the southern Cook Islands, where most of the population lives, consist of eight elevated, fertile, volcanic isles, including the largest, Rarotonga, at 67 sq km |
| Coral Sea Islands | important nesting area for birds and turtles |
| Costa Rica | four volcanoes, two of them active, rise near the capital of San Jose in the center of the country; one of the volcanoes, Irazu, erupted destructively in 1963-65 |
| Cote d'Ivoire | most of the inhabitants live along the sandy coastal region; apart from the capital area, the forested interior is sparsely populated |
| Croatia | controls most land routes from Western Europe to Aegean Sea and Turkish Straits; most Adriatic Sea islands lie off the coast of Croatia - some 1,200 islands, islets, ridges, and rocks |
| Cuba | largest country in Caribbean and westernmost island of the Greater Antilles |
| Cyprus | the third largest island in the Mediterranean Sea (after Sicily and Sardinia) |
| Czech Republic | landlocked; strategically located astride some of oldest and most significant land routes in Europe; Moravian Gate is a traditional military corridor between the North European Plain and the Danube in central Europe |
| Denmark | controls Danish Straits (Skagerrak and Kattegat) linking Baltic and North Seas; about one-quarter of the population lives in greater Copenhagen |
| Dhekelia | British extraterritorial rights also extended to several small off-post sites scattered across Cyprus; of the Sovereign Base Area land 60% is privately owned and farmed, 20% is owned by the Ministry of Defense, and 20% is SBA Crown land |
| Djibouti | strategic location near world's busiest shipping lanes and close to Arabian oilfields; terminus of rail traffic into Ethiopia; mostly wasteland; Lac Assal (Lake Assal) is the lowest point in Africa |
| Dominica | known as "The Nature Island of the Caribbean" due to its spectacular, lush, and varied flora and fauna, which are protected by an extensive natural park system; the most mountainous of the Lesser Antilles, its volcanic peaks are cones of lava craters and include Boiling Lake, the second-largest, thermally active lake in the world |
| Dominican Republic | shares island of Hispaniola with Haiti |
| Ecuador | Cotopaxi in Andes is highest active volcano in world |
| Egypt | controls Sinai Peninsula, only land bridge between Africa and remainder of Eastern Hemisphere; controls Suez Canal, a sea link between Indian Ocean and Mediterranean Sea; size, and juxtaposition to Israel, establish its major role in Middle Eastern geopolitics; dependence on upstream neighbors; dominance of Nile basin issues; prone to influxes of refugees |