What secrets lie inside the world's underwater caves and cenotes?
Mexico's cenotes connect to the world's longest underwater cave system - over 400 kilometers of passages hiding ancient Maya artifacts and ice-age bones.
The answer
The Yucatan Peninsula contains the world's longest underwater cave system, Sistema Sac Actun, stretching over 400 kilometers after its 2018 connection with Sistema Dos Ojos. These cenotes (natural sinkholes) formed when limestone bedrock collapsed, exposing groundwater. Divers have discovered 12,000-year-old human remains, including Naia - a near-complete skeleton of a teenage girl dating to the late Pleistocene. Ancient Maya considered cenotes sacred portals to the underworld, depositing jade, gold, pottery, and sacrificial offerings. Cave divers have also found giant ground sloth and mastodon fossils preserved in the crystal-clear water. Over 10,000 cenotes exist in the Yucatan, with many still unexplored. The caves contain unique species including blind cave fish and translucent crustaceans.
Source: National Geographic
- cenotes
- underwater caves
- maya archaeology
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