Cenotes
Cenotes are lakes at the Yucatan peninsula in Mexico. They occured by a collapse of the roof of caves and are mostly filled with fresh water and sometimes with salt water partially. It is supposed that the meteorite impact, who extinguished the dinosaurs, is responsible for the collapse of the roof of caves. Due to the fact that the original cave system was cluttered with stalactites and stalacmites and just a few roofs collapsed the largest (up to 250km) and maybe most spectacular cave system under water was born. The natural occupiers are besides gobies and some other also endemic basses. It is really impressive to drive by car inside the Mexican jungle, jumping in a small water hole and while the dive comes out that it is a great stunning cave system under water.
