Grotta di Su Marmuri: Sardinia’s Secret Underground World

Discover Grotta di Su Marmuri: Sardinia’s Underground Treasure

Explore Grotta di Su Marmuri, One of Sardinia’s Natural Wonders

The Grotta di Su Marmuri, located in Ulassai, Sardinia, is a breathtaking underground cave system and one of the island’s top attractions. Known for its stunning stalactites, stalagmites, and vast chambers, it offers a unique glimpse into Sardinia’s geological history.

Entrance to Grotta di Su Marmuri: A scenic view of the cave entrance surrounded by lush greenery in the heart of Ulassai, Sardinia.
Entrance to Grotta di Su Marmuri in Ulassai, Sardinia.

As you explore, you’ll notice the cave’s constant temperature of 10°C and 90% humidity—perfect for preserving its breathtaking features. One of the coolest things about the cave? If you jump on a specific spot, you can hear the water echoing beneath your feet! 😲 The water that once flowed through here sculpted the cave’s spectacular rock formations. You’ll find stunning stalagmites and stalactites, which, thanks to the minerals in the water, give the illusion of marble—but don’t be fooled, it’s all limestone!

Inside Grotta di Su Marmuri: A stunning display of massive stalactites hanging from the ceiling and stalagmites rising from the floor, showcasing nature’s artistry over millions of years.
Stunning stalactites and stalagmites inside Grotta di Su Marmuri.

Now, here’s something fascinating: during winter, the cave becomes home to one of the largest bat colonies in the area—over 25,000 bats to be exact! 🦇 These tiny bats weigh only about 7 grams each and settle here for the winter before migrating to warmer caves in the summer to breed. On our tour, we were lucky enough to spot a sleeping bat up close! Besides bats, the cave is home to five other species of creatures that live in this underground ecosystem.

Have I piqued your curiosity yet? 😉 One more thing: the cave is closed to protect the bats during winter, and no dogs are allowed inside. Oh, and there are about 1,000 steps to climb, but don’t worry—it’s all part of the adventure and 100% worth it!

Underground Pool at Grotta di Su Marmuri: A serene underground pool reflecting the soft glow of light, highlighting the cave’s breathtaking formations.
Underground pools reflecting light in Grotta di Su Marmuri, Sardinia.

This cave is truly a hidden gem, combining the beauty of nature’s artistry with fascinating geological history and wildlife. Whether you’re a nature enthusiast, a geology buff, or simply looking for a unique experience, this cave offers something for everyone.

Why Grotta di Su Marmuri is a Must-See in Sardinia

Awe-Inspiring Features

  • Impressive Chambers: The cave features enormous halls, with the main gallery extending over 1 km.
  • Dramatic Formations: Marvel at ancient stalactites and stalagmites, shaped over millions of years.
  • Crystal-Clear Waters: Witness underground pools that reflect the beauty of the cave.

A Unique Sardinian Experience

This natural wonder is not only a geological treasure but also an adventure into Sardinia’s hidden underground world. The guided tours are suitable for visitors of all ages, providing fascinating insights into the cave’s history and formation.

How to Get There

Grotta di Su Marmuri is a short drive from the town of Ulassai, and there is ample parking available. Public transportation options are limited, so traveling by car is recommended.

Practical Information for Your Visit

Visiting Days Monday–Sunday from March/April till October / November
Visiting Time Guided Tours (if in winter, best to call before going)

11:00 / 14:30 / 17:00: The tour last around 1.5 hours

Entrance Fee Adults: €12
Getting There approx 130 km from Cagliari; 2 hours by car if you leave from Piazza Matteoti

Combine Your Visit

Pair your cave adventure with nearby attractions like Ulassai’s waterfalls or the Museum of Contemporary Art Maria Lai to create a memorable Sardinian experience.

Ready to explore this amazing natural wonder? Grab your walking shoes and dive into a journey millions of years in the making!