4) Lake Natron
Lake Natron is a salt or alkaline lake located in the north Ngorongoro District of the Arusha Region in Tanzania. It is in the Gregory Rift, which is the eastern branch of the East African Rift.
The lake is a maximum of 57 kilometers (35 mi) long and 22 kilometers (14 mi) wide. Temperatures at the lake are frequently above 40 °C (104 °F) also the alkalinity of the lake can reach a pH of greater than 12. On 4 July 2001, because of its unique biodiversity the Lake Natron Basin was named to the Ramsar List of Wetlands of International Importance. Apart from sometimes turning red, there are many reasons that make Lake Natron so unusual. The alkali salt crust on the surface of the lake is also often colored red or pink by the salt-loving microorganisms that live there. ‘Alcolapia’ fish species are seen in Lake Natron. Salt marshes and freshwater wetlands around the edges of the lake support a variety of plants.