The Pit is a deep cave located in Tulum, Quintana Roo, Mexico. As part of the Dos Ojos cave system, the Pit is often visited by divers. Due to its extreme depth and the difficulties of conducting explorations in Mexico, however, the Pit has hardly been explored.

In 2009, the TRERO Dive Team visited the Pit and became addicted to its vast beauty. Over the next five years, the dive team began to systematically establish a base of operations in Tulum in order to conduct regular exploration dives into the Pit.

Follow our exploration of this wonderful cave through the videos and trip reports that are located below.

Exploring the Pit – Teaser

This video is a short teaser of the ongoing exploration Add Helium is performing at the Pit, part of the Dos Ojos cave system in Tulum, Mexico.

Exploring the Pit – Episode 1

Testing & Measuring The Add Helium Dive Team conducts a series of checkout dives into the Pitt, part of the Dos Ojos cave system in Tulum, Quintana Roo Mexico. On this trip ...

Exploring the Pit – Episode 2

Push the mainline – The Pit On this dive, the Add Helium team attempts to scooter to the end of the mainline, and explore past it. SHOW MORE

Mission Statement

The Rebreather Exploration and Research Organization utilizes the capabilities of rebreather technology to explore extreme underwater diving environments. Combining the latest scientific research vetted by our Science Council with the experience of our advanced diving team, TRERO is able to push the conventional limits of diving. TRERO’s findings are shared to educate divers and the general public.


Vision Statement

While the Oceans cover more than seventy percent of the Earth’s surface, it’s estimated that mankind has explored less than five percent. Underwater cave systems represent even greater opportunities for exploration and research. The number of known cave systems is expanding every year with no end in sight.

The vision of The Rebreather Exploration and Research Organization is to discover the mysteries of these locations. The use of advanced technology and the application of modern science are providing the means to make these efforts possible. TRERO embodies the passion of exploration with the quest for knowledge.


to continue the important underwater exploration and research

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