2. Niger River The Niger River, which is 2,600 miles long, rises on the Fouta Djallon plateau in southwest Guinea and flows through Guinea into the Mali Republic. Near Timbuktu, Mali, the Niger begins a great bend, flowing out of Mali, through the Republic of Niger, and into Nigeria. The Niger then flows south, emptying through a great delta into the Gulf of Guinea. The delta, the largest in Africa, is characterized by swamps, lagoons, and navigable channels. The Niger River is a major source of fish, in the region; especially perch and tiger fish. The upper Niger was an important part of the former empires of West Africa. The course of the Niger long puzzled European geographers; only from 1795 to 1797 did Mungo Park, the Scots explorer, correctly establish the eastern flow of the upper Niger, and it was not until 1830 that Richard and John Lander, English explorers, found that the river emptied into the Gulf of Guinea.

3. Niger River Gulf of Guinea

5. Tropical Rain Forest Tropical rain forests cover 8% of Africa and are located primarily along the equator in West Africa. Rain forests receive more than 60 inches of rain per year, with at least 2 inches falling every month. Temperatures in the rain forest are constant, rarely dipping below 70 degrees Fahrenheit or rising above 90 degrees. This warm, wet region supports the earth's most diverse and abundant flora (plant life), and is best known for its towering hardwood trees, like teak and mahogany. The constant rains wash away all of the forest floor's soil, leaving behind clay that supports the lush jungle but will not support non native plants, except in a few cultivated areas. The many fruits, nuts, seeds, leaves, and flowers produced by this dense vegetation attract a vast array of animals, many of which live in the high forest treetops. Few ungulates (hoofed animals such as horses, cattle, and deer) are present because of the deadly tse-tse fly. The bite of this blood-sucking insect carries sleeping sickness, which is harmful to humans and fatal to most ungulates.

6. Tropical Rain Forest

8. Savanna Spreading north and south from the rain-forest belt is Africa's largest and most varied climate zone: the savanna, or temperate (seasonal climate) grasslands. In areas close to the rain forests, die savanna is heavily forested. Nearer to the deserts, the grasslands are more open and are dotted only with drought-resistant acacia trees. The temperate savanna, Africa's most heavily populated region, receives its entire rainfall in one wet season, which is followed by a dry season of no rain. During the rainy period (four to eight months long), the savanna blooms with an abundance of tall, thick, rich grasses and flowering plants. During the dry season, all but the heartiest trees and bushes die away, except in the wooded savanna where forests survive year round. The savanna supports huge herds of migrating ungulates (hoofed animals such as zebras, gazelles, and giraffes), and the large predators that feed on them, such as lions and cheetahs. Heavy seasonal rains and proximity (closeness) to the rain forests provide the savanna with wide, slow- moving rivers in the west and south and a long chain of lakes in the east.

9. Savanna

11. Desert Hot, dry deserts cover nearly 30% of Africa. Deserts are located in the north and the south, isolating the interior of the continent from the northern and southern coasts. In order to reach the coast by crossing the desert, humans must survive harsh conditions. Daytime desert temperatures exceed 100 degrees Fahrenheit during the summer months, and sometimes reach as high as 140 degrees. Few people live in the harsh desert regions, where rainfall is less than 10 inches a year and evaporates quickly in the intense heat. In the Kalahari Desert, flora (plant life) is limited to hearty plants that have adapted to the lack of moisture. Trees and thick brush are located at rare water holes. Some animals are nocturnal (active at night) in order to take advantage of cooler night temperatures, while others survive by moving between scattered water sources during the day. Vast stretches of the Namib and Sahara deserts have no plant or animal life at all and are instead covered with rock or soft, shifting sand.

12. Desert Sahara Kalahari Namib Kenya-Somali