'I visited a magical underwater river and one thing caught me completely off guard'

Tacos, tequila and sombreros are just some of the clichés that come to mind when thinking of the stunning country of Mexico. But what many visitors don’t realise is that there’s a whole other world lurking beneath the surface—literally.

Not only can holidaymakers enjoy cenotes—natural water pools believed by the Mayans to have a connection to the underworld—but they can also explore an entire underwater cave system.

Remarkably, Río Secreto in Cancúnwas only discovered in 2006 by a man who was hunting in the jungle. The story goes that he chased an iguana into a hole, which turned out to be the entrance to a vast underwater oasis. In the years since, the site has been painstakingly mapped, and guides now lead around 100 tourists per day through the cave, which is full of stalactites and stalagmites.

Bats also call the cave home, along with some interesting creepy crawlies—which I, for one, tried my best not to look at during a recent trip in June 2025. Head torches are needed to see the wonders of the cave, and at one point in the tour, our guide asked us to turn them off to show just how dark it really is inside.

READ MORE: Lesser known island next to huge tourist hotspot with unspoiled beaches and crystal-clear water

The long, glittering stalactites and stalagmites are otherworldly, leaving you feeling as though you’ve landed on another planet. Some physical strength is needed to clamber over rocks and swim through parts of the cave, but nothing too strenuous.

Participants are offered walking sticks to aid with this before walking through a short stretch of jungle to reach the mouth of the cave. Inside, the cool air is a sharp contrast to the 30°C sun beaming down at the entrance, adding to the surreal experience.

Our guide, Imelda, spoke passionately about the site as we ambled along the path. She ensured everyone in our group was happy and engaged throughout. Before we began the tour, Imelda introduced us to a Mayan shaman, who gave us a blessing before we made our way down the steps into another world.

We clambered under and over rocks and even got to swim in the cool water. As someone who is claustrophobic, I was never afraid—the tall cave ceilings mean you don’t feel cramped or stuck.

The experience was magical, but one thing that caught me off guard during the visit was the strict ban on photography. GoPros are not allowed inside the cave, nor is any camera equipment, including phones—some of which tourists had placed in waterproof pouches in preparation.

Instead, a photographer accompanies the group, capturing images as you walk and swim through the trail. These are available for purchase at the end of the excursion and can be viewed on a computer screen—akin to the ones you see after a ride at Alton Towers, albeit with slightly fewer screaming faces.

However, with a price tag of around $100 (around £72) for a photo package or $30 (around £21) per person, it's a costly addition to the day. And when most of the images are of you carefully stepping over a rock in a lifejacket, helmet and wetsuit, it’s not surprising that I walked away with just the memories of such a special place.

We then made our way back to AVA Resort Cancún to end the day with a cocktail—or five—for a job well done.

Book it

Seven nights at the brand new five-star AVA Resort Cancun costs from just £1,651 per person on a premium all-inclusive basis in an Oceanfront King Room with Sea View and Balcony with two-person spa tub. Price is based on two adults sharing on an All-Inclusive Basis and includes direct return flights from London Gatwick to Cancun. Price based on select September 2025 departures. Visit AVA Resort Cancun for rooms.

A ticket to Rio Secreto is $89 (around £65) for adults and $44.50 (around £32) for children.

British Airways flights from London Gatwick to Cancun cost from £498.