First discovered by westerners in the 18th century, it is so large that no group of explorers has yet been able to confirm its dimensions. Huagapo Grotto is believed to be one of the largest caves in the world.

The cave is located on the side of the Racashmarca hillside, and visitors can make the semi-challenging hike from Palcamayo to the cave’s entrance. Once you arrive at the cave, you’ll find plenty more to admire besides its sheer size. On the walls at the entrance to the cave, you’ll see cave drawings dating back to sometime between 6,000 and 10,000 BC.

Huagapo is a Quechua word meaning “weeping cave,” so named for the underground stream of water that flows from the cave and forms a waterfall on the hillside. The water is very cold and clear. As it flows down the mountain, the waterfall trickles into a picturesque network of rivulets.

Because of the cold water, serious spelunkers have to wear scuba gear to explore the cave. You can walk 984 feet (300 m) into the cave without a guide, along a rocky ledge that protrudes from the cave wall. To go any farther, visitors need to make arrangements with a guide and bring special equipment.

Once you’ve explored as far as you can into the cave, follow the trail of the waterfall down the side of the hill, to the Racash River for more views of lush Palcamayo scenery.