Zacatón

Zacatón is a thermal water-filled cenote, or sinkhole, belonging to the Zacatón system – a group of unusual karst features located in Aldama Municipality near the Sierra de Tamaulipas in the northeastern state of Tamaulipas, Mexico. At a total depth of 339 meters (1,112 ft), it is one of the deepest known water-filled sinkholes in the world. Using an autonomous robot, the underwater portion of Zacatón has been measured to be 319 meters (1,047 ft) deep (a 20 m or 66 ft difference between the rim of cliff and surface of water adds to the total depth).

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