cenotes

Cenotes are natural sinkholes or wells formed when limestone bedrock collapses and exposes the groundwater below. They are especially associated with the Yucatán Peninsula in Mexico, but occur in other karst regions throughout Central America and the Caribbean. Cenotes range from open, sunlit pools to partially covered depressions and completely submerged cave systems.

Most cenotes form where acidic rainwater dissolves limestone, creating extensive underground channels and caverns. When the roof of these caves collapses, surface water reveals the groundwater inside. Some cenotes remain largely cave-filled with narrow openings, while others appear as broad, clear pools. They are typically connected to the regional karst aquifer and often contain freshwater; near coastal areas, mixing with seawater can produce brackish zones. Water is usually very clear due to filtration through limestone and low nutrient content.

Ecology in cenotes includes specialized organisms adapted to low light or clear water, such as cave-dwelling crustaceans and fish, along with various microorganisms. Cenotes can also preserve paleoclimate records through mineral deposits like stalactites and stalagmites, which yield information about past environmental conditions.

Cultural significance centers on the Maya, who relied on cenotes as crucial freshwater sources and regarded some as ritual sites. Archaeological finds, inscriptions, and offerings in or around cenotes reflect their historical importance and continued interest for researchers.

Tourism and conservation considerations accompany cenote use. They attract swimmers, snorkelers, and divers, sometimes within protected parks or private sites. Human activity can threaten water quality and delicate cave ecosystems, prompting management practices, access limits, guided tours, and water-protection measures. Notable cenotes include Dos Ojos, Ik Kil, and the Sacred Cenote at Chichen Itza.