It's located in Africa, and takes its name from the ancient Kingdom of Congo. Amazing numbers here: the Congo river is the deepest river in the world, surpassing in several zones 220 meters. With an average of more than 40.000 cubic meters per second, it's very interesting in terms of renewable energy, with near forty active hydro-power plants!
For having as much depth, you could guess that has more than a million years and that's correct! The river has a great quantity of endemic species making the location unique and always a warranty of seeing something new.
But be aware of a dangerous species called hydrocynus goliath or more commonly giant tigerfish. This is one of the most dangerous freshwater fish, carnivore, with some reaching 1.5 meters or more. There are documented attacks to humans because the creature could bite us in theory by mistake.
The Congo river permits navigation, providing almost fifty thousand kilometers of routes, used especially for transportation of people and goods. With some luck, you could visit one of its four thousand islands!