This is the lake that turns birds into stone. Lake Natron is a shallow salt and soda reservoir in Tanzania, near the border with Kenya. It is extremely dangerous. The temperature can reach 140F and its pH level is 10. The water is so caustic it can burn the skin and eyes of animals that aren't adapted to it, according to Live Science. And deposits of sodium carbonate also act as a preservative, leaving the dead animals looking mummified. The lake is, however, a safe breeding place for flamingos.