Diving an UNEXPLORED cave in Mexico!

Coming up, Jonathan and Todd team up with cave explorer Robby Schmidtner to survey a new section of cave in Mexico. Welcome to Jonathan Bird's Blue World. So our friend Robby Schmidtner is surveying a new cave, or new section of cave, I'm not actually sure which. And he invited us to make an episode about it, but he also needed some footage of it for his project. So it sounded like a win-win. So today we're going to a secret cave, we don't even know where it is, we're meeting him on the side of the road, and we're going to go see his research project. So that is going to be cool. My understanding is where we're going, is Robby's project involves an extension of the Huitzilopochtli system, which is part of the largest underwater cave system in the world. And so we are following our GPS to the secret location. Robby Schmidtner is one of the world's top cave explorers. We did an epic dive with him into a cave that was so newly discovered that it didn't even have a name. We had a great time, and I guess we passed the competency test because Robby invited us back to the Yucatan for a cave exploration adventure. Which leads us to the mysterious rendezvous point. On the side of the road, it's a clandestine meeting. How are you sir? What's going on? Soon we're following Robby into the jungle. We drive a dusty dirt road for a good half hour. Eventually, Robby stops in the middle of nowhere. We follow him into the jungle on a freshly cut path. Soon we arrive at a tiny hole in the ground. It's only big enough for one person at a time. He calls it Wishing Well. I love your handmade ladder. How anyone finds a tiny cenote out in the middle of all this jungle is a mystery to me. But Robby found it. We begin the process of gearing up for a long dive with a tricky entry. Okay, just in case. So much fun. Here we go. Mapping a cave requires a lot of line, so he has to load up a big exploration reel. And now I know why he invited us. Robby has a lot of faith. A little more tension. What? More tension? Oh, the suit is almost dry. With our tanks down by the cave, it's time to don the sidewinders, side mount rebreathers that will allow us as much as 6 hours underwater. Robby has an electric winch run by a small generator to get the equipment into the cenote. We have to go one at a time, so we make Todd go first. All right Todd! Woo hoo! First Todd has to don his tanks down in the water. Okay, she's coming down. When he's ready, the camera goes down last. At the bottom of the hole, there's a pile of forest litter. Decades of organic stuff falling in from above. Todd will wait alone in the dark for us. Lowering my own stuff into the hole. Once Todd has submerged, it's my turn. Eventually I arrive in the cave. Now Todd and I will have to wait for Robby. Because the entrance is tight and vertical, and the sidewinder is designed to breathe best in a horizontal cave diving trim, Robby suggested that we go through the chimney on open circuit and switch to the rebreather down below. He turns on his oxygen and signs to us O2 on. Then he switches to his rebreather. And we're off on our way, leaving the entrance chamber that we silted up a bit. Within only a dozen fin kicks, we've reached crystal clear water. The nice thing about diving rebreathers is there's no rush. We have plenty of air. And no bubbles to disturb the ceiling. When Robby first dove this cave, he found some line already installed from another entrance thousands of feet away. But the section of cave near the Wishing Well entrance was barely explored because it's so far. Soon we reach a spot on the main line where there is a side passage Robby wants to explore. So he ties in with the big exploration reel. We almost immediately enter into an incredibly beautiful section of cave. We are very likely the first people to ever see this passage. What an incredible privilege to be in such an unspoiled place. During the last ice age, when the ocean levels were much lower, the water table was lower too, and this cave was filled with air, not water. Dripping water over thousands of years left behind a tiny amount of minerals in the shape of all these amazing formations. Stalactites, stalagmites and columns. Soon Robby finds a restriction. You never know what amazing stuff might be back behind a tiny restriction, so you have to go look. After a squeeze and a short swim, it turns out to be a dead end. So we backtrack. Not every lead is productive. In cave diver lingo, we would say, it doesn't go. But we found another possible passage. And this one goes. On the floor of this section are the remains of pools. Dripping water from above collected into pools on the floor, which evaporated, leaving behind mineral gardens. We also find the remains of a small animal that wandered in and never left. We've gone as far as we're going today, so Robby has me cut the line and he ties it off. He even lets me put a line arrow on there. My name is now on this passage. How cool is that! Normally he would survey the line on the way out so he can add it to his map. But he has a few other places he wants to show us, so he leaves the survey for another day. This cave is one of Robby's favorites, so we get a tour. Soon we come to a jump between two lines. Because some of the line in this cave was laid without knowledge of the Wishing Well entrance, a lot of the line arrows don't point to the entrance we used. It's really important to use markers to be sure we find the right way out. We enter one beautiful section after another. Todd and I are getting spoiled by this amazing cave. Some of the formations blow my mind. There are coralloids, often called cave popcorn, growing on some of the stalactites. They are caused by evaporation. Moving into another section, we keep a careful eye on all the fragile stuff. Everywhere we look, there is dripstone and popcorn. And a tiny column, growth frozen in time by rising water levels. Robby leads us into room after room of wonders. Without bubbles crashing into the ceiling and raining down particles, the water stays nice and clear. Some of the rooms are large enough to swallow all the light we have. Robby is using a pair of big blue 30,000 lumen lights, as bright as modern car headlights. But this is a big room. We swim beneath what appears to be a thousand menacing swords. Finally, it's time to head back. We reach our jump reel and spool it up, retracing our steps to the entrance. Back at the Wishing Well entrance, Robby heads out first so he can assist with getting the gear out of the hole. Todd heads up next since he has been down the longest. Robby broke one of the rungs on his jungle ladder, so Todd rides the winch out of the hole. Then it's my turn, after more than three hours underwater. And I discover that riding the winch is not actually that pleasant. I'm often asked what it is I love about cave diving. It's peaceful. It's beautiful. It brings out my inner 12-year-old exploring a mysterious place. I love the adventure of it. This dive was all of those things, but also something else. Something much more rare. We saw a beautiful place for the first time. Not just the first time for us, but the first time for anyone. We were the first human beings to ever see an unexplored passage of this cave. There are not many places left on our planet where that's possible. And that is one of the most special experiences in the Blue World. If you are an advanced cave diver and you want to take your cave diving to the next level, contact Robby for an adventure. His details are down below.