Lac de Gafsa, also called 'Mysterious Lake', is a recently formed body of water alongside Om Laryes Road, 25 kilometers from the town of Gafsa in Tunisia.
Since the lake was discovered in 2014 by desert shepherds, Lake de Gafsa has become a curiosity for locals, and an overnight international tourist sensation. Hundreds have gone just to see the lake, to dive off the picturesque rocks and swim in the lake, and / or scuba dive in it since its discovery.[2]
Testing for radioactivity
The area is rich in phosphate and there are fears the water could be carcinogenic as it might contain radioactive residue. The water is now[when?] undergoing testing by experts for contamination; however, at present[when?] there is no official ban from swimming in the new lake. The lake, which is estimated to be between 18 and 20 meters (59 to 65 feet) deep, has changed from its clear turquoise blue color (as discovered) to a slightly murky green, meaning the fresh flow of water has ceased and the water is now stagnant.[3]
https://www.youtube.com/watch?v=jPIo-yxUDlQ
