Lake Nyasa, or Lake Malawi, is the third largest lake of Africa and the southernmost among those of the Great Rift Valley.

It forms part of Malawi’s boundary with Tanzania: it has an overall length of 560 km and it is 75 km wide. With its 700 m depth Lake Nyasa is one of the deepest lake in the world.

https://www.spaziosafari.com/en/tanzania/lakes/2018/09/05/lake-natron-and-ol-doinyo-lengai-volcano/