Sac Actun cave system
Area: Nohoch Nah Chich
Length: 256,909 m
Maximum depth: 101.2 m
Exploration
1987 - James G. Coke
Original exploration. Jim and Thomas M. Young later produced and published the original map, documenting 14,200 ft of water-filled cave.
1988 - James G. Coke, Johanna DeGroot, Steve DeCarlo, Richard Ribb, Thomas M. Young, C. Goulet
Explored and surveyed (compass and line survey). Length 10,200 ft; completely underwater.
1989-11 - James G. Coke
Discovery of the Snake Cenote in downstream Sac Actun.
1993-05 - Dan Lins
Penetration of the "Twister Restriction"; Dan Lins then led the downstream exploration.
1996-04-11 - Sam Meacham, Bil Phillips
Connection from the upstream Calimba section to Paso de los Pozos, through the "Boa Restriction".
1996-12 - Chuck Stevens, Dan Lins
Discovery of the "Road to Sac", during the 1996 Sistema Naval project (Dan Lins, Mike Madden, Andreas W. Matthes, Chuck Stevens).
1997-05-22 - Bil Phillips, Daniel Riordan
Discovery of the "Trap Door" (farthest upstream Sac Actun): 7,566 ft of new cave.
1998 - Daniel Riordan
Exploration of the "Hour Glass" section. Dates as given on the map: 1998-03 - 1998-04.
1998-03-12 - Bil Phillips
Discovery of "Lithium Sunset".
1999-03-13 - Dan Lins, Bil Phillips
Connection of Sac Actun and Sistema Naval, bringing Sac Actun to 56,034 ft. Section explorers: Si Bi Beh (Bernd Birnbach, Steve Gerrard, Pablo Diaz, Kate M. Lewis, Bil Phillips, Daniel Riordan), Tum Ben Beh (Bil Phillips, Daniel Riordan), Calimba (J. Gonzales, M. Heusick, Sam Meacham, K. Olsen, Bil Phillips, J. Smith), Lithium Sunset (Bernd Birnbach, Bil Phillips, Daniel Riordan, Christophe Le Maillot, J. Walker), Hour Glass (Bil Phillips, Daniel Riordan, E. Martinez), Historic (H. Ayala, G. Coulet, James G. Coke, Richard Ribb, S. De Carlo, P. Parker, J. De Groot, Thomas M. Young, John Zumrick), Siphon (James G. Coke, E. Fiorelli, Woody Jasper, Dan Lins, B. Messersmith, Bil Phillips, C. Pyle, Andreas W. Matthes, J. Walker), Naval (B. Gavin, Hilario Hiler, G. Irvine, Dan Lins, Mike Madden, Andreas W. Matthes, Chuck Stevens).
2007
Connection of the Nohoch Kin-Muul Ha and Nohoch Nah Chich regions ("2007 Connection"): 154,783 m, depth 71.6 m.
2011
Connection with the Aktun Hu region ("2011 Connection"): 217,495 m, depth 107.2 m. The map also marks the 1999, 2004 and 2007 connections.
2012
Sac Actun and Dos Ojos shown as one system: length 303,356.8 m, depth 125.2 m (October 2012).
2012-08 - Don Arburn, Gill Ediger, Aida Ferreira, Devra Heyer, Carrie Hutchins, Pat Kambesis, Chris Lloyd, Rene Rogers Ohms, Bev Shade, Peter Sprouse, Terri Sprouse, Germán Yáñez Mendoza, Jacinto Vela
Suunto and laser rangefinder survey of the Pet Cemetery area.
2015-09 - Dombrowski, Douglas Franquemont, Bil Phillips
Caves
- Alkab Ha
- Azteca
- Balan Ku
- BFR
- Big Cenote
- Bosh Chen
- Boveda
- Box Chen
- Calimba
- Capak
- Cenote of the Bones
- Colapse Cenote
- Coralillo Falso
- Dirty Dog
- Dos Palmas
- Dos Plumas de Toh
- Estaca
- Four Doors
- Gorila
- Grand Cenote
- Ho-Tul
- Hope
- Isla Perdida
- Jaguar
- Ka'as
- Lil's
- Lunas y Sombra
- Mosquitos
- Naval
- Nicte-Ha
- Opening 1
- Opening 2
- Opening 3
- Opening 4
- Opening 5
- Opening 6
- Pabilanny
- Pet Cemetary
- Por One
- Pozo Profundo
- Sabalo
- Sardinas
- Shake
- Sin Nombre
- Snake
- Tak Be Luum
- The Pit
- Vainilla Norte
- Vainilla Sur
- Xibalbá
- Yax Kin