Cool shimmering water engulfs you, and cathedral-like caverns open up around you.
Illuminated only by the headlamp on your helmet, the caverns reveal clusters of multicolored stalactites, hanging like petrified icicles from the craggy cave ceiling.
As if that were not surreal enough, the scene is all reflected on the glasslike surface of the blue-green water all around you.
Billed as a “Mayan Underground,” the natural phenomenon located about an hour south of Cancun in Playa del Carmen lives up to its slightly mysterious aura. As you traverse the twisting route of the river, you’ll be immersed at times in absolute silence and pitch darkness.
Still, visitors are put at ease by the knowledgeable tour guides who shepherd their groups through the narrow passageways and deep pools of water. Along the way, the guides seamlessly weave in the cave’s history, culture, and ecology.
Rio Secreto’s website emphasizes the uniqueness of the natural reserve.
“Rio Secreto could well be one of the natural wonders of the world,” it states, adding that touring the river, with its thousands of stalactites and stalagmites, is “like stepping back in time to witness something mysterious and truly spectacular.”
Along with its magnificent sights, a tour of the natural reserve comes with a few conditions and restrictions. Based on the information I gathered during a sponsored press trip to the area, here are some of the things to expect on a voyage into the underground world of Rio Secreto.
Rio Secreto Is Deep In The Jungle
Before you set foot in the massive cave that is Rio Secreto, you will take a bumpy ride in a van on a dirt road through the jungle of Riviera Maya.
While the main entrance to the attraction is located just off of the Cancun-Tulum Federal Highway 307, you’ll be transported from there by van for about 5 miles to a spot near the mouth of the cave.
It pays to stay alert during the ride, because tropical flowers intertwine with the thick undergrowth alongside the road, and you might even spot jaguars and iguanas.
After arriving at the cave site, you’ll take a fairly easy 10-minute hike through the jungle to get to the mouth of the underground river.
Swimming Suits Are Required
As you wait for your van ride at Rio Secreto’s main entrance, a recorded message will fill you in on the details of your coming cave tour.
Among the rules: “Inside the underground river system, you will not need to wear anything other than your bathing suit and prescription glasses, if required.”
Since you will be in the water for virtually all of the tour, from 3 hours to all day, a swimming suit certainly makes sense.
Because you will be putting on a wetsuit over your swimming suit, a comfortable, athletic-style swimming suit is recommended.
Everyone Must Take An Outdoor Shower
Once you have changed into your swimming suit and stowed your other items in an assigned locker, you’ll be required to take an outdoor shower.
The Rio Secreto instructions explain that this is because it is vitally important to preserve the purity of the water. Visitors are asked to refrain from applying any chemical products to their skin, and the showers are required to ensure that any remaining sunscreen, insect spray, or other cosmetic products are removed.
No Cameras Are Allowed
Among the items you are required to leave behind in your locker are your camera and cell phone.
“For your safety and for the preservation of the river, you are not allowed to carry cameras or wear watches, earrings, or other accessories,” the introduction explains.
Once you’re inside the cave, the reason becomes obvious. It would be nearly impossible to carry a camera or phone while wading through waist- and shoulder-deep water. And camera flashes would be distracting for others on the tour.
There’s no need to worry that you won’t have pictures from the tour. Excellent professional photographers accompany the tourgoers and take multiple shots of each participant, as well as the group, at numerous scenic spots along the route.
Special Expedition Equipment Will Be Provided
After you’ve taken a shower, you’ll line up to be fitted for your wetsuit, life vest, and helmet.
Each of these items is crucial. The wetsuit will help to protect you from the cool water and rocky walls of the cave, while the life vest will be important in the deeper sections of the river. The helmet will keep you from hitting your head on the cave’s low ceilings and overhangs, and it also comes equipped with a headlamp that will light the way through the dark cave.
For extra help traversing the rocky sections of the riverbed and gauging the depth of the water, the wooden sticks that are provided (but not required) also come in handy.
You'll Experience A Mayan Smoke Ceremony
As you approach the mouth of the cave, a Mayan shaman will conduct a smoke ceremony to cleanse you before you enter the sacred cave.
The short ceremony offers fascinating insight into Mayan culture and the important role that the region’s caves and cenotes (sinkholes) have played in Mayan history.
It’s Pitch Black Inside
Although the headlamp on your helmet will always be available to use, there are times on the tour when the guide will ask you to turn off your light.
At those times -- like when the group members are instructed to float on their backs in a circular formation -- expect moments of complete darkness. No light pollution here -- the darkness is stunning.
The Cave Terrain Is Rough And Uneven
Like the floor of any river, the floor of the Rio Secreto can be rough and rocky at times. Although the guides do their best to point out approaching high steps and deep holes, the route can get a little treacherous.
To help navigate the river, sturdy water shoes are recommended. Visitors can either bring their own or use the ones provided by the tour.
The River Gets Deep
While the tour is mostly navigable on foot, there are sections that are too deep for walking. Those areas, near the end of the tour, will require some brief floating/swimming.
But since all participants are required to wear life vests, the deep sections should be doable for non-swimmers.
Conservation Is Central To Rio Secreto
On its website and in its promotional literature, Rio Secreto emphasizes the preservation aspect of its mission.
The audio introduction for visitors refers to the underground river as a “unique, fragile world that only a few people will have the opportunity to experience during their lifetime.”
It adds that the reserve’s driving force is conservation.
“By visiting us, you are participating in our passion to preserve this incredible natural beauty,” the introduction says, adding that a significant percentage of the entry fees go toward the preservation of the underground river, local plants and wildlife, water quality studies, and a variety of environmental-education programs.
As visitors prepare to take the van ride to the cave, the introduction concludes: “You are about to discover our planet’s deepest undiscovered territory. Keep your eyes and hearts open so that what you see will remain forever imprinted on them.”
A Variety Of Tours Are Available
Tours can be booked online on the Rio Secreto website and range in price from about $79 to $119. A variety of times, durations, and experiences are on offer.
Some tours include just admission and a buffet lunch, while others include additional activities such as rappelling, snorkeling, and biking. Transportation from local hotels can also be added on.
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