underground lake

An underground lake is a body of water that exists beneath the Earth's surface, often within caves or beneath layers of rock and sediment. These lakes form when water from rain, rivers, or snow infiltrates the ground and becomes trapped in natural underground cavities or porous rocks. They can vary greatly in size and depth, sometimes connected to larger aquifers or other subterranean water systems. Because they are hidden beneath the surface, underground lakes are not visible from above and require exploration or specialized equipment to study. They are important for groundwater supplies and can also host unique ecosystems.