Things to Do›Caves, Rivers & Tubing
02 · Caves, Rivers & Tubing
Arenales Caves & Charco Azul.
A cave system, a swimmable river canyon, and a waterfall — three landscapes in one day, all in the part of the island most visitors miss.
The Activity
Three landscapes, one driver.
Puerto Rico has karst country — limestone cliffs eaten through by rain over millions of years, leaving caves, sinkholes, and underground rivers. The Arenales caves are one of the better-known systems you can walk through, with chambers lit by sunlight from above and bats sleeping out the day in the corners.
After the caves, you'll head into the Charco Azul canyon — different from the tubing trip a few miles upstream — and swim through pools to a waterfall set into the rock. Lunch is on the way, the drive is scenic, and you're back in Santurce before dark.
Why people love it
Variety. Most full-day tours give you one experience stretched thin. This one is structured like a sampler: a cave, a river, a waterfall, in that order, each one different enough to be its own memory. Groups with mixed energy levels do well here — there's something for the hiker and the casual swimmer in the same trip.
Why I love it
The caves are quiet. Genuinely quiet — once you're inside, the air is cool and still and you can hear your own footfalls. After a few days of San Juan traffic, it resets your hearing. And then you walk out into bright sunlight, full canopy, and a river you can swim in. It's a good kind of whiplash.
Pro tips
- Bring a flashlight or use your phone's torch in the cave — the guides have lights but a backup is nice.
- The cave floor is wet. Trail-runners or aqua shoes only.
- Don't touch the formations. Skin oils stop them from growing.
- You'll swim — bring a swimsuit and a quick-dry layer.
- The drive back is the best part of the day if you nap. Window seat.
- Phone in a dry bag. Pictures inside the cave are good but the air is humid.
The logistics
- Duration: about 7 hours with transport
- Difficulty: moderate — walking, light scrambling, swimming
- Group size: small to medium
- Pickup: from San Juan / metro area
- Distance from the house: about 90 minutes west
