Sistema Sac Actun (, ) is an underwater cave system situated along the Caribbean coast of the
Yucatán Peninsula
The Yucatán Peninsula ( , ; ) is a large peninsula in southeast Mexico and adjacent portions of Belize and Guatemala. The peninsula extends towards the northeast, separating the Gulf of Mexico to the north and west of the peninsula from the C ...
with passages to the north and west of the city of
Tulum. Discovery of a connection to
Sistema Dos Ojos
Dos Ojos (officially ) is part of a flooded cave system located north of Tulum, on the Caribbean coast of the Yucatán Peninsula, in the state of Quintana Roo, Mexico. The exploration of Dos Ojos began in 1987 and still continues. The surveyed ext ...
in 2018 made it the longest known underwater cave system. , it is the second longest underwater cave system in the world, only surpassed by
Sistema Ox Bel Ha.
The remains of a
mastodon
A mastodon, from Ancient Greek μαστός (''mastós''), meaning "breast", and ὀδούς (''odoús'') "tooth", is a member of the genus ''Mammut'' (German for 'mammoth'), which was endemic to North America and lived from the late Miocene to ...
and a human female that might be the oldest evidence of
human habitation in the Americas have been found in the cave.
History of exploration
Exploration started from ''Gran
Cenote'' west of Tulum. The whole of the explored cave system lies within the
Municipality of Tulum, in the state of
Quintana Roo
Quintana Roo, officially the Free and Sovereign State of Quintana Roo, is one of the 31 states which, along with Mexico City, constitute the 32 administrative divisions of Mexico, federal entities of Mexico. It is divided into municipalities of ...
.
In early 2007, the underwater cave
Sistema Nohoch Nah Chich was connected into and subsumed into Sac Actun making it the
longest surveyed underwater cave system in the world. Sac Actun measured (after connecting with ''Sistema Aktun Hu'' ((in January 2011) and is, with an explored length of , only surpassed by the
Sistema Ox Bel Ha at .
Since early 2007, these two caves have frequently exchanged the title of world's longest underwater cave.
Including connected dry caves makes Sistema Sac Actun long, the second longest cave in Mexico
and third longest worldwide.
On December 9, 2004, after a dive with two other teammates, Kent Hirsch and Michael Nast were drowned deep in the cave as they got lost and exhausted their oxygen supply.
In 2018, the discovery of a link between the Sac Actun system (reported to be long) and the
Dos Ojos system in Tulum, Quintana Roo ( long) was reported. The connection was found by the Gran Maya Aquifer Project (GAM), led by the cave diver and explorer Robbie Schmittner.
The combined system is reported to be the world's second longest underwater cave system known.
Upper Paleolithic remains
In March 2008, three members of the ''Proyecto Espeleológico de Tulum'' and
Global Underwater Explorers dive team, Alex Alvarez, Franco Attolini, and Alberto Nava, explored a section of ''Sistema Aktun Hu'' known as the ''Hoyo Negro'' pit.
At a depth of the divers located the remains of a
mastodon
A mastodon, from Ancient Greek μαστός (''mastós''), meaning "breast", and ὀδούς (''odoús'') "tooth", is a member of the genus ''Mammut'' (German for 'mammoth'), which was endemic to North America and lived from the late Miocene to ...
, as well as a
human skull at that might be the oldest evidence of human habitation in the Americas.
Additional bones were located and the skeleton was later identified as that of a teenage female now referred to as
Naia.
See also
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References
* Steve Gerrard (2000). ''The Cenotes of the Riviera Maya''. .
online Version'. Retrieved January 14, 2011.
{{Recreational dive sites, cavsit
Sac Actun
Caves of Mexico
Landforms of Quintana Roo
Limestone caves
Sinkholes of Mexico
Tulum (municipality)
Natural history of Quintana Roo
Paleoanthropological sites
Underwater diving sites in Mexico
First 100 IUGS Geological Heritage Sites