Why The 2 Idiots recommend visiting Slovenia’s Postojna Caves?
We discovered the Postojna Caves simply because we were visiting Croatia and rented a car to drive between PorecandZagreb, Croatia. There are two paths to get there: one that drove through Croatia and the other that took a little longer but went through Slovenia. We took that path because we wanted to visit another country. We had no idea what was out there and luckily discovered these cool caves in the town of Postojna, Slovenia.
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Pronounced post-troy-na, the caves were described as Gringotts from the Harry Potter books and movies, and Natasha is a huge fan of Harry Potter and when she saw these caves in person, she agreed – they are massive, beautiful and remain vividly in her head as one of the most beautiful places she has visited. For me, I have seen a lot of cave systems and been on a lot of cave tours, but felt these were, by far, the most incredible, expansive caves I have ever seen. The size of the formations, the scale of the caves – it’s humongous and amazing. This is a must-visit!
CREATING AN IDEAL ITINERARY
Drive from Porec to Zagreb by following the Slovenia route, stop in Postojna along the way. It’s just an hour and a half to the caves, and then another two hours to Zagreb, so you can leave Porec in the morning, arrive in Postojna for lunch and the 2.5-hour tour, and then continue on to Zagreb to arrive by evening.
Logistics
We rented a car that we took from Porec and dropped off in Zagreb. When driving a car from Croatia into Slovenia, you need a special border crossing card that you’ll need to get certified at the border, which can create long lines at the border crossing. It may sound complicated, but it is very easy; just stop before you reach the border and purchase the special pass.
Tickets to the cave tours are available online, yet we found they were different from what is available at the guest center. We purchased tickets in advance and were rushed thinking we wouldn’t make it on time for our tour, but when we arrived, we discovered there were other tours available and we could relax, eat lunch and then join a later tour.
Exploring the Caves

A train takes you up to the caves – again, very Gringots! It is about a 20-minute train ride, which happens to be the world’s only doubletrack cave trainway, and your children will love riding the train. As you ride the train into the caves, you’ll enter a massive dance hall with a large chandelier made with Murano glass from Venice that made Natasha think of a Dracula movie. You’re in the middle of these caves and yet here is this hall, lit up by the massive chandeliers!
When you arrive to the caves, you will find they are moist and chilly, and it can get slippery. Be sure you’re wearing the right shoes and layered clothing to make the tour more enjoyable. Once you are inside, it is absolutely amazing. At every turn there are cool formations, illuminated so you can see the caves yet creating shadows that amplify the experience. It’s breathtaking and so difficult for us to describe the beautiful, haunting experience of walking through these caves – even the photos don’t do it justice.

You will be walking a lot, but large strollers are forbidden and you’ll need a very small, compact stroller to do the tour, which is about a mile in length and will take about an hour and a half. There were some spaces that got a little scary for using the stroller and we had to take our son out and adjust, but the entire tour is child-friendly and there are a lot of children, so don’t let this deter you.

The tour guides will explain the cave system, which is the second-largest in Slovenia at more than 24,000 miles. The caves were formed by the Pivka River and cave drawings date as far back as the 1200s, although the caves were first discovered by modern man in the 17thcentury. The caves became a tourist destination in the early 1800s when Archduke Ferdinand, the Emperor of Austria-Hungary, began to visit the caves and opened them to the public. During the first World War, Russian prisoners were forced to construct a bridge that connects the largest chasm inside the caves. In World War II, Germans used the caves to store aircraft fuel, until Slovene Partisans destroyed them in 1944, creating a fire that burned for a full week and destroyed portions of the cave. Today, more than 1 million people visit the caves every year. (Fun fact: The caves house the only underground post office in the world!)

You’ll be stopping for photos so much that the tour may continue without you and you’ll have to hurry to catch up, but don’t worry, everyone is doing this, too.

At the end of the tour is a vivarium with translucent snake-like fish that do not like light, so it’s difficult to see the fish in the dark vivarium but when you see them, you can see through the fish into its body – so very cool! Known as Olm, these endangered creatures lack pigmentation, making its organs visible. Light can actually kill Olm, so please do not use flash or your camera lights to try to get a better view. After the vivarium is a gift shop and then you take another train ride back. It was such a tranquil visit that we sat at the onsite café and had a drink and just talked about what we saw. It’s a wonderful stop to break up a long drive, but worthy of a visit even without a drive.
KID-FRIENDLY TIPS
- Even if it’s warm outside, the caves will be chilly. Wear warm clothes or bring clothes to layer as you do into the caves.
- Get lunch/food prior to the tour, as it will take 2.5 hours. It’s a cave; there isn’t anything inside for snacks, so be sure to carry snacks and milk with you.
- Due to the train portion of the tour, as well as some tight spaces when walking, large strollers are not allowed and you will be asked to leave them for the tour. However, our stroller was small enough and folds to fit into a bag so we were able to bring our stroller, which we recommend.
OTHER TIPS
- Buy tickets online so you can reserve your tickets
- They have a cafe on site so you can eat lunch before your tour, and grab drinks after the tour.
- You will want to wear sneakers and good shoes since there is a lot of walking and some of it can be slippery without the right shoes.
- Be careful of raising your hands to take pics or videos while the train is moving – in many sections the caves isn’t high and you might hit your head on the top of the caves, and you also may lose your phone.
- Don’t put a light on the translucent snake-like fish called Olms. Olms lack pigmentation so its organs can be seen and light can hurt these endangered creatures.