Cenotes are natural sinkholes or wells that are filled with water, commonly found in the Yucatán Peninsula of Mexico. They are formed when limestone bedrock erodes, creating openings that expose groundwater. Cenotes can vary in size and depth, and they often feature clear, fresh water that is popular for swimming and diving. These unique geological formations were significant to the ancient Maya civilization, who used cenotes for water supply and as sacred sites for rituals. Today, cenotes attract tourists and adventurers, offering opportunities for exploration, snorkeling, and experiencing the region's natural beauty.