These destinations offer kayakers a unique adventure: underground paddling

Descending into a chasm on the side of an eastern Kentucky mountain might not sound like an epic start to a kayaking expedition. Yet, here in the heart of the Red River Gorge Geological Area, a 29,000-acre canyon system home to sandstone arches, cliffs, and abandoned mines, it is the best way to experience water without the crowds.  

With U.S. kayak sales up nearly 25 percent from pre-pandemic levels as of March 2023, congested lakes and rivers have become the norm. This trend doesn’t seem to be slowing down, with the global kayaking market projected to approach one billion dollars by 2031.  

Yet, for those seeking tranquility on the water, there remain undiscovered havens—hidden beneath the surface.

Exploring the depths below

Our guide, JP Stamper, leads down into a chilly cavern with a life jacket, helmet, and paddle in hand. Flashlights flicker on as we navigate around icy water cascading from the mine’s ceiling, 40 feet above. Venturing deep underground on water might seem daunting to some, but there’s an overwhelming sense of calm that accompanies floating over still water, in surreal silence.

For 90 minutes, we paddle through winding chambers and expansive caverns, our clear-bottom kayaks revealing huge boulders and rainbow trout below. Overhead, tiny Kentucky brown bats are nestled deep in their winter hibernation. Here and there, wires and pipes—remnants of a once-thriving mining industry—appear eerily preserved beneath the water’s surface.

At no point during the SUP Kentucky kayaking tour did it feel claustrophobic. In the parts of the tour with the deepest water, paddlers rise within about six feet of the overhead rock. The absence of any current and the presence of our two guides on stand-up paddleboards monitoring our group also helps.

Subterranean kayaking might not be at the top of the list for most paddlers, but for Don Marsan, who runs kayaking tours from the massive, 150-acre underground lake at Crystal City Cave in Missouri, there’s nothing like it. “We’ve had thousands of people from all over the world come here to try this out. We do about 20,000 people a year,” he says.

SUP Kentucky saw a 26 percent increase in visitors between 2021 and 2023. Last year, it started offering unguided kayaks and paddle board tours to meet the demand from more adventurous paddlers.

“We take them in, show them around, and then leave them be for two hours,” says Stamper. “But people can’t get lost—there’s a light trail that leads all the way back to the entrance.”

(These trails aren’t for hikers, they’re for kayakers.)

The company also offers the choice between a clear-bottom kayak or a paddleboard with multicolored LED lights illuminating the water underneath.

At the Blue Springs Cavern Park in Bedford, Indiana, kayakers can navigate America’s longest navigable underground river with a local tour company that offers three-hour kayaking and boat trips 100 feet below the surface.

Where to try underground kayaking

Subterranean kayaking isn’t limited to the U.S. In Korea’s Dongyang (also known as Chungju) Jade Cave, visitors can paddle in the cool, damp underworld. In Belize’s Nohoch Che’en Caves Branch Archeological Reserve, tour operators offer kayaking and tubing through caves where ancient Mayan culture is depicted on cave walls.

A 450-year-old former metal mine in northern Slovenia has become a hotspot for underground kayaking.

“We had 2,100 people in 2021, last year we had 3,371, despite being closed for three weeks due to flooding in August,” says Darja Komar, the manager of Podzemlje Pece, a tour operator at the mine.

Visitors take a short train ride down the mine before walking 328 feet through hip-high water to reach the kayaks. From there, paddlers spend 45 minutes on tandem kayaks, navigating through 1.7 miles of tunnels and open spaces. The guided tours are in English, German, and Slovenian, with each tour limited to 10 participants.

(See the ocean’s glow-in-the-dark world on a fluorescent night dive.)

“It’s not just a tour,” says Komar, “it’s an experience where you learn about the history of mining and this region.”

For some, exploring subterranean water worlds from a kayak is adventurous enough, while others have taken it to another level.

The Rio Chontalcoatlán in Mexico’s Grutas de Cacahuamilpa National Park offers one of the most challenging whitewater kayaking adventures. Expert kayakers navigate nearly two miles of underground rapids and narrow passages, guided only by tiny lights on their helmets—a venture best suited for the most skilled whitewater paddlers.