Underwater Cave Exploration in Tulum: New Discoveries in Cenote Darth Vader
Darth Vader's Depths [ Part two]
Unveiling a Hidden Underwater World
Into the Abyss: First Descent and Initial Discoveries
After pulling the regulator apart and clearing out the diaphragm, the regulator seemed to breathe ok. So I descended down, apprehensive but excited. Dropping through the dark, tannic stained water, I ran my line as carefully as I could through fallen tree branches, trying to find the cave entrance. And then popping through the gap between the rock ceiling and the leafy slope of the cenote I was in. The walls were non existent as I shone my light around, and as I continued into the cavern the floor dropped away. It was a massive space, intimidatingly large. I later measured that where I made my six meter tie off for safety or deco stops, the floor was twenty meters below that! The tunnel was very clearly defined and big, so I wasted little time in reeling off into the cave. After a few shots, I knew I was onto something big, and that the reel would be empty quickly! Remembering I wanted to save some line to scout the second cenote, I tempered my enthusiasm and reluctantly cut the line at a break down at the end of a massive tunnel. I could see that there was a huge space at the top of the boulder pile but would leave that for the next dive. Surveying out, I took my time to look around. The tunnel was very defined and big, with some huge, ancient looking columns and stalactites. I marked a few potential leads for more exploration and arrived back into the cavern.
The Cavern Zone: A Gateway to the Unknown
Over the course of many dives at this cenote I became familiar with the cavern zone. First, it was the entrance and exit to the cave tunnel so every dive passed through here. But the line that had been laid on the first dive might not have been in the best place - this is sometimes the case that on subsequent dives you will notice that there might be a better routing of the line for ease of travel or to keep divers away from more delicate formations. Strangely, here rather than choosing to take the time to reroute the line from open water into the cave, we had to do it. Many of my dives at Darth Vader were made with Phillip Lehman from the Dominican Republic Speleology Society. One of the days we arrived ready to continue the exploration, the mainline in the cenote was nowhere to be found. Running a reel down from the surface we found the line on the bottom, it had been cut! And the arrow detached and was thrown into the water too. Despite the strangeness of the event, we used the opportunity to reroute the mainline, and set up a deco station. With the average depth of the line at 17 meters, and much of the cave at between 20 and 24 meters in the salt water, decompression obligations build up and it’s good to have a comfortable place to leave oxygen tanks and hang while the minutes tick by.
A Downstream?
Interestingly, with such a large cave passage, and cavern zone, there is no downstream. Or at least not one which goes far… One day while hanging out on my deco stop, I was bored, and decided to look around the cavern for anything interesting: bones, pots, or more cave. While I didn’t find pots or bones, I did notice that in one corner of the cave the flow was siphoning into a restriction. Subsequently I made a couple of attempts to squeeze through, but even with both tanks taken off, I was not able to fit through. During these attempts I spent quite a bit of time in complete zero visibility - any contact with the cave here silted it out completely - but it quickly cleared up with the flow… One day, with smaller tanks I would like to try again!
The Main Passage: Massive, Ancient, and Ever-Expanding
Returning after that initial dive was an exciting prospect. Would the cave continue? What would happen on top of the breakdown? Winding the way up through collapsed boulders, the space at the top looked bigger and bigger. Popping up, it was clear this was a big room! Next was to see if the tunnel continued on the opposite side of the room, or there was a way down (it had shallowed up from 18 meters to 14). And continue it did! Coming down the slope the tunnel was wide open! We continued to push and lay line, before the tunnel ended in another breakdown. This one was easier to navigate up through and cross over to continue along the massive main passage. Again after nearly 100 meters we hit another break down. This one was a bit more difficult to navigate through - and as the dives were to get bigger and use Dive Propulsion Vehicles (DPVs or underwater scooters) we eventually made a bypass to be able to fit through easier. Descending down the slope, the tunnel continued to open up and dropped deeper the further in we went. Down in the salt water the cave was a brilliant white. We continued to lay line along what seemed to be the continuation of the main tunnel, which progressively got deeper.This is exploration where being on a rebreather makes a difference! We used our Sidewinders to really push the exploration here, not being limited by open circuit gases we could really spend time to find where the cave continued.
The cross over tunnel
Things were going well, big beautiful cave tunnel, lots of good tie offs. But then rather than shallowing up into a breakdown collapse as had been the trend, the cave started to pinch down and the tunnel seemed to end. We tried to find a way to continue but each time we only found small tunnels that didn’t go very far. Back tracking a bit, Phillip began to lay line into a smaller side tunnel, ducking under a ledge to get into it. This very unpromising start began to pay off! While it constantly looked like the cave was going to end, the tunnel continued until, popping through a restriction we ended up in another massive tunnel! As the dives continued, it was clear that there were two parallel freshwater / salt water tunnels, connected through a deeper cross over tunnel.
Documenting the Depths
While we were exploring the cave Phillip also filmed an episode of Somos Los Cenotes here. The Somos Los Cenotes project is an idea not only to show the beauty of the caves in the area to non-divers, but also to demonstrate the economic benefits of cenote diving to the local economy. While we were actively exploring Darth Vader, the plan to build the controversial Tren Maya was still being discussed. The Tren Maya was intended as a regional rail network to loop the Yucatan Peninsula and link the three states of Quintana Roo, Yucatan and Campeche. This project was controversial as it did not follow the normal environmental impact studies, include much discussion with stakeholders and was rushed through by presidential decree. Initially, in the area, it was planned to run alongside the 307 highway (where caves had been damaged already) but pressure from hotels on the government resulted in it being shifted kilometers into the jungle (and on top of some of the longest underwater cave systems in the world). Now in 2025 it is a completed project (for good or ill) but in 2020 / 2021 it was hoped that pressure could influence where the final train line would be run - unfortunately it was built over, and between many of the cave systems. Darth Vader’s far ends of line are now under the train line.
Darth Vader Revealed
So after initial equipment troubles, I dove and began the exploration of this cave. Cenote Darth Vader is an unusual, for Mexico, single entry cave without much side tunnel development. Over the course of the exploration the team found 3.2 kilometers (10,500 feet) of new cave, which I hope might grow bigger. Most of the exploration was done using closed circuit rebreathers, specifically the KISS Sidewinder, for longer durations and less percolation. The cave is quite different from many of the other caves nearby, and I expect the same water is flowing through Darth Vader into neighbouring systems. Dark and spooky, the cave can be enjoyed on the Somos Los Cenotes channel, as it is not accessible for diving currently.
Curious about training for exploration or survey dives like these?
Have a look at my Overhead Courses, or feel free to reach out if to start your own journey into cave diving in Mexico’s cenotes.
Photos of Darth Vader by Phillip Lehman for the Somos Los Cenotes project.
