You’ve been charmed by the streets of Ljubljana and awestruck by the alpine wonders of Bled. But your visit to Slovenia isn’t complete until you’ve experienced at least one of the top 5 caves in Slovenia.

Here are the top tips from Terry Anzur, a Slovenian-American journalist at the blog Strangers in the Living Room:

  1. Postojna Cave: something for everyone
  2. Predjama Cave Castle: world’s largest cave castle
  3. Škočjan Caves: UNESCO heritage underground
  4. Pivka Cave: adventure for thrill-seekers
  5. Idrija Mercury Mine: deep dive into history

Which Slovenia cave adventure is right for you? In a country with hundreds of caves in Slovenia, there’s something for everyone: Natural beauty, fascinating history, epic adventure and even a Disneyland-style train ride.

The speedy train ride through Postojna Cave makes a Slovenia cave adventure accessible for travelers of all ages and abilities.
The speedy train ride through Postojna Cave makes a Slovenia cave adventure accessible for travelers of all ages and abilities. Photo courtesy Iztok Media for Postojna Cave Park.

Postojna Cave: Accessible Slovenia Cave Adventure

If you have time for only one Slovenia cave adventure, make it Postojna Cave. This natural wonder has been wowing visitors for more than 200 years. In 1818, a local lamplighter stumbled into the cave and declared: “Here is paradise.”

More than 40 million people have visited Postojna Cave since then. It is the third most visited attraction in Slovenia, after Ljubljana and Bled. At times, you might have the feeling that you’re in a cave-themed amusement park. Don’t despair if there’s a line to board the train; it moves quickly.

The 3.7 km train ride makes the most astounding chambers and galleries accessible for all ages and abilities. Don’t miss the vast Dance Hall, lit by Murano glass chandeliers. There is an optional 1.5 km walk to the iconic “Brilliant” formation.

Be sure to stay seated on the train as it whips past the overhead rocks with deadly speed. Please respect nature by not touching the formations. They formed over millions of years, one drop of water at a time.

For maximum enjoyment, put down your camera. In the low light, your phone photos are likely to be disappointing. Flash photography is not allowed. Professional photographers need permission to set up lights.

Join this Postojna Cave tour from Ljubljana!

Postojna Cave in Slovenia
Visitors to Postojna Cave have the option of staying on the train or taking this short walk through vast galleries to view the iconic rock formations. Photo courtesy Iztok Media for Postojna Cave Park.

Slovenia’s Baby Dragons

Kids will love seeing the “baby dragons,” a unique species in Postojna Cave. The olms can live for 100 years and can survive a decade without food. Buy a separate ticket to the Vivarium to learn more about all the creatures of the underground world.

When to Visit: Postojna Cave is open 365 days a year. There’s an underground nativity scene during the holidays. Bring a warm jacket because of the constant 10-degree Celsius temperature, year-round. To avoid the summer crowds in June, July and August, arrive when the cave opens at 9 am. The big tour groups arrive later in the morning.

Getting there: Postojna Cave Park is an easy day trip from Ljubljana or Bled, by car or bus. Reserve tickets online or buy at the ticket office.

Pro tip: Stay at the Hotel Jama to skip the ticket line and get a discount on tour packages. Camping in the area is also popular. There’s a parking lot for motorhomes. There’s even a free kennel where your pet can wait while you tour the cave.

Predjama Castle: Mighty Slovenia Cave Fortress

Predjama Castle, the world’s largest cave fortress, is only a short drive from Postonja Cave. You can easily visit both on the same day with a combined “Two Adventures” ticket or combined tour.

Many group tours only stop for the insta-worthy photo opportunity of the Slovenia cave castle emerging from solid karst rock. But you should plan to go inside and learn the fascinating history.

The 15th Century knight Erazem withstood a siege for more than a year by smuggling in fresh food through the cave tunnels. Sadly, he didn’t survive a cannonball that struck the castle at its most vulnerable point: the toilet.

Make a wish as you ring the castle’s bell. It was used to warn of approaching invaders. You only have to admire the view of the surrounding countryside.

Pro tip: Get the Predjama Castle audio guide for a vivid description of life in the Middle Ages as you walk through the torture chamber and weapon rooms.

Predjama Castle Slovenia cave adventure
Go inside the iconic Predjama Cave Castle to visit the caves that made it possible to hold off an invading army for more than a year.

Škočjan Caves: UNESCO heritage Slovenia Cave

For a more natural Slovenia cave experience, visit the Škočjan Caves in Slovenia. UNESCO has organized a guided tour that presents the underground world heritage while respecting the environment.

You’ll be awestruck by the underground cathedrals, carved out over the centuries by the Reka River. Photography is not allowed for most of the tour inside the caves. Near the exit, there is a picture opportunity that conveys the majesty of what you have just experienced.

Sturdy hiking shoes are a must, as well as a jacket for the underground chill. Be prepared for slippery pavement and hundreds of steps. This adventure is not recommended for small kids or those with mobility concerns.

Getting there: You can visit Škočjan Caves on a day trip from Ljubljana by car. Buy tickets online or at the ticket office. Horse lovers may want to add a stop in nearby Lipica, home of the Lipizzaner horses you may have seen performing in Vienna. Bicycle tours of the karst region are another great option.

Pro tip: Allow some extra time for an extended hike through the karst landscape and the charming village of Škočjan. Hiking trails are well marked, starting from the end of the cave tour.

Škočjan Cave adventure Slovenia
Škočjan Cave guided tour and extended hike exploring the stunning scenery of the karst region in Slovenia. Photo courtesy Terry Anzur.

Pivka Cave: Adventure for Thrill Seekers

If you came to Slovenia for a high-octane adventure, you’re in luck. With a little planning ahead, you can book an adrenalin tour in the vast underground of Postojna Cave Park. All of the special equipment you will need is included in the price of the guided tour.

The Luka Čeč tour in Pivka Cave is named for the lamplighter who discovered the cave system in 1818, but toiled in poverty for decades before getting the credit he deserved. Be prepared for rappelling down rock faces, slogging through mud and paddling through an underground lake.

Exploring the caves in Slovenia
Book in advance to experience a thrill-seeking Slovenia cave adventure, like this tour of Pivka Cave. Photo courtesy Terry Anzur.

You also have a chance to spot the baby dragons and other unique cave species in their natural habitat. This adventure was so epic for my family of three that it deserves its own movie, as you’ll see in this video:

The Bat Cave under the Castle

A less demanding adventure allows you to explore the Windy Hole and other passageways underneath Predjama Castle. Different versions of this guided tour are suitable for older kids and teens.

But beware of bats! The consistent year-round temperature makes the castle caves a hibernating spot. Tours must be reserved in advance from May to September, when the bats are awake.

Pro tip: Fuel up for your adventure at Gostilna Požar, a friendly mid-priced restaurant serving Slovenian specialties with a picture-postcard view of Predjama Castle.

Idrija Mercury Mine: Underground History

History paired with caves in Slovenia! This tour covers 500 years of UNESCO world heritage in the 700 km of mercury mine tunnels underneath the town of Idrija. Anthony’s Shaft is the oldest preserved mine entrance in Europe.

The tour begins with a movie about the hard lives of the mercury miners. A guide wearing a mine foreman’s uniform takes you into the tunnels. You’ll see the numbered medallions miners wore during their shifts on the “death clock.” They stopped at an underground chapel to pray for a safe return.

Miners kept up their spirits with strong drink. They believed the mine was haunted by a mischievous elf who would lead them to the quicksilver — or worthless rocks. Idrija prospered as it became one of the largest mercury mines in the world. Unfortunately, the wealth did not trickle down to the poorly paid miners.

The miners worked without safety equipment until modern times. How many died from mercury poisoning and related illnesses? All of them. But you’ll be perfectly safe in the warm jacket and protective helmet included with the tour. Expect lots of walking on slippery surfaces and stairs.

Idrija Mercury Mine Tour Slovenia
Miners wished each other “good luck” before beginning a long hard day in the Idrija Mercury Mine. Photo courtesy Terry Anzur

Find out more in this video:

Idrija Dumplings and Lace

Above ground, the miners’ wives kept busy with lacemaking, a tradition that continues today. The handcrafted lace sold in the local shops makes a beautiful souvenir to take home.

Don’t forget to try the traditional Idrija dumplings called žlikrofi. Served with hearty sauce, they were a filling meal for the hard-working miners. The most popular restaurant is Gostilna Pri Škafarju, just a short walk from the entrance to the mine tour, but the dumplings are served in many of the local eateries.

Getting there: Idrija can be reached by car on a day trip from Ljubljana. Find tour times and ticket information on the website.

Pro tip: If you have more time, visit Gewerkenegg Castle, which looms over the narrow streets of the small, friendly town. It’s filled with exhibits about the history of mercury mining and lacemaking in Idrija.

Planning a trip to Slovenia? The biggest mistake you can make is not allowing enough time for all of the nature and history that is packed into this small country – the caves in Slovenia in particular. It’s a miniature version of Europe in one clean, green, sustainable package.

Dobrodošli! Welcome.

Are you staying in Ljubljana while in Slovenia? Check out our video of things to do in Ljubljana:


  • Terry Anzur

    Terry Anzur is a Slovenian-Polish-American TV journalist. She writes about travel on Strangers in the Living Room, a blog inspired by her work as an international media trainer. Her travel tips help you feel at home anywhere in the world.

    View all posts Terry Anzur is a Slovenian-Polish-American TV journalist. She writes about travel on Strangers in the Living Room, a blog inspired by her work as an international media trainer.