Africa is the second largest continent on Earth, covering approximately 11.7 million square miles (30.4 million square kilometers), which accounts for about one-fifth of all land on the planet. It stretches roughly 5,000 miles from its northernmost point on the Mediterranean coast to its southern tip at the Cape of Good Hope, and about 4,600 miles at its widest from east to west. That enormous span means Africa contains nearly every type of landscape and climate found anywhere on Earth, from the world’s largest hot desert to dense equatorial rainforests to snow-capped volcanic peaks.
The Sahara and Africa’s Desert Regions
The single most dominant geographic feature of Africa is the Sahara Desert, which covers roughly 3.3 million square miles across the northern third of the continent. To put that in perspective, the Sahara is nearly as large as the entire United States. It stretches about 3,000 miles from the Atlantic Ocean in the west to the Red Sea in the east, and between 800 and 1,200 miles from north to south. The Atlas Mountains and the Mediterranean Sea form its northern boundary, while its southern edge blends into the Sahel, a semiarid transitional belt that separates true desert from the wetter savannas to the south.
Despite its reputation as endless sand dunes, only about a quarter of the Sahara is actually sandy. Much of it consists of rocky plateaus, gravel plains, and dry valleys. Temperatures swing dramatically within a single day: surface temperatures can exceed 130°F in the afternoon and drop below freezing at night. That daily temperature swing is actually greater than the difference between the hottest and coolest months of the year.
Southern Africa has its own significant desert regions, including the Namib along the Atlantic coast and the Kalahari, which is technically a semi-desert since it receives slightly more rainfall. These southern deserts are much smaller than the Sahara but ecologically distinctive, with the Namib considered one of the oldest deserts on Earth.
Mountains and Highlands
Africa is often thought of as a flat continent, and large portions of it are relatively level plateau. But it has dramatic highlands and peaks, particularly along its eastern edge. Mount Kilimanjaro in Tanzania is the tallest mountain in Africa at 19,341 feet (5,895 meters). It’s a dormant volcano made up of three volcanic cones, and it holds the distinction of being the highest freestanding mountain above sea level in the world, meaning it rises directly from the surrounding plains rather than being part of a mountain range. Despite sitting just south of the equator, Kilimanjaro’s summit carries glaciers, though they have been shrinking rapidly.
The Ethiopian Highlands in the northeast are sometimes called the “Roof of Africa” and form one of the continent’s most extensive elevated regions, with peaks above 14,000 feet. In the northwest, the Atlas Mountains run through Morocco, Algeria, and Tunisia, separating the Mediterranean coast from the Sahara. East Africa also features a string of volcanic mountains along the Great Rift Valley, including Mount Kenya (17,057 feet) and the Rwenzori Mountains along the border of Uganda and the Democratic Republic of the Congo.
The Great Rift Valley
One of the most striking geological features on Earth cuts through eastern Africa from the Red Sea down through Mozambique. The Great Rift Valley is a series of connected trenches formed by tectonic plates pulling apart, and it stretches more than 3,700 miles. In some places the valley floor sits thousands of feet below the surrounding plateau, with steep escarpments on either side.
The rift system created many of Africa’s great lakes. Lake Tanganyika, the second deepest lake in the world at over 4,800 feet deep, fills a section of the rift. Lake Malawi and Lake Albert also sit within rift basins. Lake Victoria, Africa’s largest lake by surface area and the world’s second largest freshwater lake, lies between the two branches of the rift rather than inside it. These lakes are critical freshwater sources for hundreds of millions of people across eastern and central Africa.
Major Rivers and Drainage
The Nile River is the continent’s most famous waterway and one of the longest rivers in the world at approximately 4,132 miles. Its drainage basin touches 11 countries: Egypt, Sudan, South Sudan, Ethiopia, Eritrea, Kenya, Uganda, Tanzania, the Democratic Republic of the Congo, Rwanda, and Burundi. The Nile flows northward, which is unusual for a major river, emptying into the Mediterranean Sea through a broad delta in northern Egypt. Its two main tributaries, the White Nile and Blue Nile, converge at Khartoum in Sudan.
The Congo River in central Africa carries more water than any other river on the continent and is second globally only to the Amazon in discharge volume. It drains the vast Congo Basin, an area of dense tropical rainforest that represents the second largest rainforest on Earth after the Amazon. The Niger River curves through West Africa in an unusual boomerang shape, flowing northeast into the Sahel before turning southeast toward the Gulf of Guinea. In southern Africa, the Zambezi River is best known for Victoria Falls, one of the largest waterfalls in the world, on the border between Zambia and Zimbabwe.
Climate Zones From North to South
Africa’s climate follows a broadly symmetrical pattern on either side of the equator, driven largely by the seasonal movement of a weather boundary called the Intertropical Convergence Zone. This is where moist air masses from the ocean meet dry continental air, and its position shifts north and south throughout the year, bringing rain with it.
At the equator, particularly in the Congo Basin and along the coast of the Gulf of Guinea, rainfall is heavy and nearly year-round. Temperatures stay warm and consistent, and dense tropical rainforest thrives. Moving away from the equator in either direction, you enter the tropical wet-and-dry zone, often associated with savanna landscapes. This zone covers just under half of Africa’s total surface area, making it the continent’s most widespread climate type. It features a distinct rainy season when the convergence zone is nearby and a dry season when it shifts away.
Farther from the equator, the climate becomes semiarid. These regions receive some rainfall but not enough to support dense vegetation. The Sahel south of the Sahara is the most well-known example. Beyond the semiarid belts lie the true deserts: the Sahara in the north and the Namib and Kalahari systems in the south. At Africa’s northern and southern tips, the climate shifts again to Mediterranean conditions, with mild wet winters and warm dry summers along the coasts of Morocco, Tunisia, and South Africa’s Western Cape.
Savannas and Rainforests
The African savanna is the landscape most people picture when they think of the continent: wide grasslands dotted with scattered trees, particularly acacias and baobabs. Savannas cover enormous stretches of East Africa, including Kenya’s Maasai Mara and Tanzania’s Serengeti, as well as large portions of West and Southern Africa. These grasslands support the highest density and diversity of large mammals found anywhere on Earth, from elephants and giraffes to wildebeest herds that number in the millions.
Central Africa’s tropical rainforests are a very different world. The Congo Basin rainforest spans roughly 700,000 square miles across six countries and stores vast amounts of carbon, making it globally significant for climate regulation. Unlike the open savanna, the rainforest is dense, humid, and layered, with a canopy that blocks most sunlight from reaching the forest floor. It harbors extraordinary biodiversity, including gorillas, forest elephants, and thousands of plant species found nowhere else.
Coastline and Surrounding Waters
For a continent of its size, Africa has a relatively smooth coastline with few deep natural harbors, peninsulas, or large inlets. This is a notable contrast to Europe, which has a highly irregular coast with many natural ports. Africa’s coastline runs roughly 18,950 miles, bordered by the Mediterranean Sea to the north, the Red Sea and Indian Ocean to the east, and the Atlantic Ocean to the west.
The island of Madagascar, off the southeast coast, is the world’s fourth largest island and is often considered part of Africa’s geography despite being separated by the 250-mile-wide Mozambique Channel. Its long isolation from the mainland produced extraordinary biodiversity, with roughly 90% of its wildlife found nowhere else on Earth. Other notable island groups include Zanzibar off Tanzania, the Canary Islands off northwest Africa, and the volcanic Cape Verde archipelago in the Atlantic.