There's a deceptively still body of water in Tanzania with a deadly secret - it turns any animal it touches to stone. The rare phenomenon is caused by the chemical makeup of the lake, but the petrified creatures it leaves behind are straight out of a horror film.
Lake Natron is fed by the Southern Ewaso Ng'iro River and also by mineral-rich hot springs. It is quite shallow, less than three metres (9.8 ft) deep, and varies in width depending on its water level, which changes due to high levels of evaporation, leaving behind a mixture of salts and minerals called natron.
(thanks Michael and Stanley)