Sistema Nohoch Nah Chich

Sistema Nohoch Nah Chich (from Spanish and Yucatec Maya meaning "Giant Birdcage System"), is located 16.5 kilometers (10.3 mi) south of Akumal in Tulum Municipality of Quintana Roo state, southeastern Mexico. It is part of the Sistema Sac Actun underwater cave systems. It is an extensive water filled cave system connected with the Caribbean Sea, fed via a coastal spring in a cenote with a variety of names, including Cenote Manati, Cenote Tankah, and Casa Cenote after a nearby restaurant. The explored cave system extends to approximately 8 kilometers (5.0 mi) inland from the coast. Sistema Nohoch Nah Chich was discovered to be connected to the Sistema Sac Actun, making the Sac Actun the longest surveyed underwater cave system in the world.

Cave data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).