Lake Tanganyika is the second deepest lake in the whole world. Its deepest point is about 1,470 metres — that is deeper than most mountains are tall. The lake is also very long, stretching 673 kilometres from north to south. That is roughly the same as driving from London to Edinburgh and back.
The water is famously clear and blue, almost like the sea. Because the lake is so deep, the top layer and the bottom layer barely mix, which means the fish living near the surface have been cut off from relatives elsewhere for millions of years. Scientists have discovered hundreds of fish species that live only in this one lake and nowhere else on Earth.
For the people of Burundi, Lake Tanganyika is a treasure. Fishermen set out each evening in wooden boats with lanterns to catch ndagala — tiny silvery fish — and return before sunrise. The lake also provides swimming, transport, and a stunning view of the sunset that turns the whole surface orange and pink.
Hippos wade along the shallow edges at dusk, and African fish eagles soar overhead watching for a meal. On clear mornings you can sometimes see the mountains of the Democratic Republic of Congo on the far shore — more than 50 kilometres away across the water.