Barra Honda has a fascinating cave system with limestone reefs that look pretty cool. These reefs started forming about 60 million years ago due to some tectonic action. Over time, they've turned into a bunch of separate caves with awesome stalactites and stalagmites inside.
 

Currently, only about half of these caves have been explored by scientists and cave enthusiasts. But don't fret, you can still experience the adventure by visiting Velvet Cave, which is open to regular folks looking for some thrills. It's a safe option for both newbies and seasoned cave explorers.
 

Your adventure begins with a pleasant hike through the forest. When you reach the cave, they'll outfit you with the right gear and lower you down a ladder into the cave's depths. You'll have about an hour to explore and check out formations that took millions of years to shape.
 

Just a heads-up, though: if you've got high blood pressure, get dizzy easily, or don't like tight spaces, it's probably best to skip this adventure for safety reasons.