A cave is a natural underground space large enough for a human to enter. Caves are formed through various geological processes, including erosion by water, volcanic activity, or the dissolution of soluble rocks like limestone. They can vary in size and shape, often featuring unique formations such as stalactites and stalagmites. Caves provide important habitats for many species, including bats, insects, and various plants. They also hold archaeological significance, as they can preserve ancient artifacts and fossils. Famous caves, like Carlsbad Caverns in the United States and Lascaux in France, attract visitors for their beauty and historical importance.