Lake Tanganyika is not only the longest lake in the world, but also a freshwater Mecca. Part of the Great Rift Valley, the lake cuts across 420 miles (675 km) of East Africa and divides four nations. In total, the lake covers about 12,700 square miles (20,439 square km) and serves as Africa’s largest freshwater reservoir and the second largest in the world.
Considered one of most biologically rich lakes on Earth, Tanganyika is home to more than 2,000 species, more than half of which aren’t found anywhere else. And, according to the World Conservation Union, “no place on earth holds such a variety of life.”
At somewhere between nine and 13 million years old, it’s also one of the oldest. Thanks to its age and ecological isolation it’s home to an exceptional number of endemic fish, including 98% of the 250-plus species of cichlids. Cichlids are popular aquarium fish due to their bright colors, and they make Tanganyika an outstanding snorkeling and diving destination.
It occupies the southern end of the Western Rift Valley, and for most of its length the land rises steeply from its shores. Its waters tend to be brackish. Though fed by a number of rivers, the lake is not the center of an extensive drainage area. The largest rivers discharging into the lake are the Malagarasi, the Ruzizi, and the Kalambo, which has one of the highest waterfalls in the world at 704 feet (215 m). Its outlet is the Lukuga River, which flows into the Lualaba River.