Lake Tanganyika: Africa, 420 miles, second-deepest, diverse aquatic life, vital resource.

Lake Baikal: Siberia, 395 miles, world's deepest, unique ecosystems, natural wonder.

Lake Superior: North America, 350 miles, largest freshwater, stunning landscapes, recreational.

Lake Malawi: Africa, 365 miles, rich biodiversity, clear waters, African Rift.

Lake Michigan: North America, 307 miles, second-largest Great Lake, beautiful shores.