There is a lake that is a giant crater - Apparently.
Lake Hillier, located in Western Australia, is a saline lake that is contained within a giant volcanic crater. Measuring approximately 550 meters in diameter and 50 meters deep, the lake's vibrant pink color is due to the presence of high concentrations of algae and bacteria. Despite its unusual appearance and surroundings, Lake Hillier is a natural and relatively stable geological feature, attracting tourists and scientists alike.