Caves are natural underground spaces formed by various geological processes, such as erosion and volcanic activity. They can vary in size and shape, ranging from small openings to vast networks of tunnels. Caves often contain unique features like stalactites and stalagmites, which are formed by the deposition of minerals from dripping water. Many caves serve as habitats for diverse wildlife, including bats and cave-dwelling insects. Some famous caves, like Carlsbad Caverns in the United States and Lascaux in France, are known for their stunning formations and ancient rock art. Caves also play a significant role in scientific research and exploration.