Marcelin Nebenhaus, Marcelin Cave Diving, Under the Jungle, Marcelin Under the Jungle



• TDI Cave and Side Mount Instructor
• From Paris, France
• In Mexico Since 2015
• Languages: French, English, Spanish


As a child, I dreamed of becoming an underwater archeologist. The vast portion of our planet is underwater, and it fascinates me because I am sure there are mysteries left to discover. While I am not an underwater archeologist, I have realized my childhood dream in a way. I feel fortunate to be able to explore new caves, and sometimes even find historical artifacts inside them.

I have been an avid diver since 1995, and my adventures in diving have taken me to a wide variety of environments. But for me, nothing in the world compares with cave diving. From the moment I first swam into a cavern, I was completely hooked! I spent years just diving and learning the caves in Mexico for fun before I even became a cave instructor. And I still love every moment under the ground!


Cave diving is peaceful, silent, and profoundly beautiful, and for me it has been a great passion from the very start. Mexico’s caves are endlessly fascinating, and I am amazed by the diversity of features and types of caves in the Riviera Maya. Taking the time to learn the intricacies of a cave system is a pleasure, and exploring a new cave is a privilege. There are few things I enjoy more than diving every known tunnel in a cave, understanding the flow of water, the geology, and where the next passage leads. It’s like solving a very complex and amazing puzzle.


The psychological aspect of cave diving is also fascinating, and learning to control my mind and body at such a high level has pushed me to grow tremendously as a diver and as a person. I enjoy the precision and level of training associated with the activity, and despite the fact that I had been diving for many years before I started cave diving, building that mindset and skills to be a cave diver took my diving to a completely new level. The journey to become a good cave diver is difficult, but worth it.



I have always associated diving with the idea of exploring unknown places. The feeling of being in a flooded cave that has never been visited by anyone with dive line in my hand is thrilling. It takes a lot of mental control to slow down and analyze what lays in front of you when you find yourself in that situation. You have to take the time to build the needed experience and skills to approach it in a controlled and relaxed manner. When you are able to lay the line, take the survey data and finish your dive with an empty reel it is all worth it!


Of course exploration is also about the journey to the cave. Being out in the jungle for hours at a time, spending the day with friends and debriefing everything when you are done. Whether the exploration is a success or not is of little importance in the end, it is all about sharing and growing as a diver and instructor. Exploring the underworld is as much about self exploration as anything else.



I advocate progressive penetration. This is the concept that you get to know a cave system little by little, over many dives. You take many references and notes, with the goal of truly understanding the cave system. That idea applies to technical and overhead diving in general. If you take the time to train well and increase the complexity of your gear and dives progressively, you will be amazed by what you can accomplish. As an instructor I also believe in building my own confidence and skills in that manner. Take the time to do things right, keep diving, and keep practicing and you will accomplish more than you though possible!