Postojna Cave is Slovenia’s most popular tourist attraction, and Predjama Castle the most famous and unique castle in the country.

One is a natural wonder and the other is a man-made feat of medieval engineering that will leave you wondering how it is even possible.
If you are using Ljubljana as a base, a day trip to Postojna Cave and Predjama Castle has to be one of the best day trips you can do from the capital.
The Queen of All Caves, and the largest cave castle in the world are definitely worth a visit as a day trip or while travelling through Slovenia. They are both located within the Park Postojnska Jama, so it’s very easy to combine them on the same day.
Table of Contents
How to get to Postojna Cave from Ljubljana

Postojna Cave is located in the town of Postojna, only 46km from Ljubljana and it’s very easy to get to.
Trains run every hour from Ljubljana Train Station to Postojna. It takes approximately one hour and it costs €5,80 (~$6.50) each way. From the train station it’s a 30-minute walk to Postojna Cave.
Buses are roughly every hour too, with less frequency in the evenings. The journey also takes approximately one hour and it costs €6 (~$7) one way or €10.80 (~$12) return. The bus drops you off at the cave park, so you don’t have to walk far.
Alternatively, here is a Postojna Cave and Predjama Castle tour from Ljubljana that takes care of your transportation and your entry ticket to both, so you don’t have to worry about anything.
RELATED POST
2 Day Itinerary in Ljubljana
Postojna Cave

Postojna Cave is a pretty spectacular 24km long limestone cave that has been carved by the Pivka River over a period of 3 million years. The accessible area is almost 6km long, 4km of which are done by electric train, and the remaining 2km on foot through purpose built walkways.
To get to the walkways, you need to take the now famous electric train. This is the first and only underground train of its kind in the world. It’s a fun ride, but if you are tall, watch out for the lower sections of the tunnels!


While you explore the cave, you will come across all sorts of incredible natural formations. Our guide explained that stalactites grow downwards by water dripping from the ceiling through the deposit of calcite, which builds up to create these shapes.
Stalagmites are those that grow upwards, building from the drips above, and columns form when a stalactite and a stalagmite join together.
And within these formations, you will find others such as spaghetti stalactites or curtains. There really are endless shapes that you can encounter here. It’s a real wonder.



Postojna Cave has just celebrated 200 years since its discovery, so installations have been improved, but its popularity has increased too.
A top tip would be to arrive for the first tour of the day at 9am. We were about 15 people in the English language tour group, but on peak hours on busy days it can get up to 200 people per group! So get there early to make the most of it!



The cave tour takes 90 minutes. Make sure you wear comfortable footwear and warm clothes, as the temperature in the cave is around 10 C degrees all year round.
Life in Postojna Cave

The cave is home to ‘baby dragons’, otherwise known as olms. Olms are aquatic salamanders that live underwater in caves. They are blind and with pale skin, with underdeveloped eyes and no pigmentation.
People used to believe that these olms were the offspring of a dragon living in the depths of the cave. You can see these baby dragons in Postojna Cave’s Vivarium.
Ticket Prices for Postojna Cave
- Postojna Cave only – €25.80 (~$30) in low season / €27.90 (~$32) in high season.
- Postojna Cave + Vivarium + Predjama Castle – €41.90 (~$48) in low season / €45.60 (~$52).
I would recommend the combined ticket for the three attractions to get the most out of the experience.
Another option would be to book a full tour from Ljubljana that takes care of transportation from your hotel and the entry tickets.

Postojna Caves Opening Hours
The Postojna Cave Park is open all year round, but the number of daily tours for the cave will vary according to the season.
Between May and September there is an hourly tour starting at 9am all the way through to 5pm (July and August until 6pm).
The rest of the year will vary across different months. You can check more details here.
How to get from Postojna Cave to Predjama Castle
In July and August there is a free shuttle bus that goes between Postojna Cave and Predjama Castle. Outside of these two months, a return taxi costs €30 (~$34), which is not too bad if you are travelling with a couple of friends.
Another alternative would be to hitchhike, which is what my friend and I did. It did take a few minutes to get a ride but as it was the end of June there were a few tourists driving between the two attractions.
I would not recommend hitchhiking on your own though. I wouldn’t do it myself.

As I mentioned earlier, if you don’t want to worry about transportation, you can join a tour from Ljubljana, which will also include the tickets to both Postojna Cave and Predjama Castle.
RELATED POST
Glamping in Bela Krajina, Slovenia
Predjama Castle

Predjama Castle matches the image of the ultimate fairytale castle in a fairytale setting.
Built in an impossible place, the castle is perched up in the middle of a vertical 123-metre high cliff face, jutting out of a cave. It is the quintessential image of a medieval castle, complete with a mini drawbridge.
The only preserved cave castle in the world, Predjama Castle is also holds the Guinness World Record for being the largest cave castle in the world.


On arrival you will be given a free audio guide, which will help you with learning and understanding the history of the castle.
Built in the 15th century, it was the hideaway of the rebellious knight Erasmus, the Slovenian Robin Hood. Inside you will learn the story behind this legendary Slovenian hero and how he was eventually betrayed by one of his soldiers.


It’s pretty impressive to see how it was built and how the man-made walls of the castle blend in with the rock face and the cave. And its strategic location means that the views from the castle over the valley are pretty spectacular and add to the idyllic setting.


There’s a torture chamber in the castle, which makes it a bit eerie. In fact, you could hear prisoners being tortured throughout the castle. Imagine that as your background noise. There is also an armoury room that exhibits medieval armours and weapons.


When you get to the top of the castle, make sure you ring the bell and make a wish.
There is a cave at the back of the castle that it is said to connect with a village a fair distance away. This is, allegedly, how Erasmus used to get provisions during his time in hiding.
I climbed up the steps in the cave as far as I could and the environment was humid, cold and dark. It was really interesting to see how ingenious they were, in setting up a system that collected the water that filtered through the rocks.


Under the castle, there is a network of cave passages more than 14km long that reach behind the castle too. It is an important archaeological site that dates back to the Stone Age. To access the cave here you would need an additional ticket, which you can buy onsite.
Ticket Prices for Predjama Castle
- Predjama Castle only – €13.80 (~$16) in low season / €14.90 (~$17).
- Postojna Cave + Vivarium + Predjama Castle – €41.90 (~$48) in low season / €45.60 (~$52).
As mentioned above, I would recommend the combined ticket for the three attractions to get the most of the experience.
Another option would be to book a full tour from Ljubljana that takes care of transportation from your hotel and the entry tickets.

Predjama Castle Opening Hours
Predjama Castle is part of the Postojna Cave Park, which is open all year round, but the opening hours for the castle vary according to the season.
Between May and September the castle is open from 9am to 6pm (July and August until 7pm).
The rest of the year will vary across different months. You can check more details here.
Staying in Postojna Cave Park
Another great way to make the most of the Park Postojnska Jama, is by staying overnight. Hotel Jama is located right in the middle of the Park, so it’s very convenient for further exploration before the crowds arrive and after they leave. You can check the best deals for Hotel Jama here.
Have you visited any similar caves or castles around the world?
Let me know in the comments!
- Plan your trip to Slovenia with these guidebooks.
- Get the best deals on flights with Skyscanner.
- Find the perfect place to stay on Booking.com.
- Discover more about Slovenia through local experiences.
Like this post? Pin and save for later


Disclosure: A big thank you to Park Postojna Jama who hosted me on this trip. As always, all views are my own.
Bryan
Tuesday 8th of June 2021
Bonjour, Je viens de visiter des grottes similaire aujourd'hui, les grottes du Drach au îles baléares. C'est magnifique et très impressionnant !
Teresa Gomez
Friday 18th of June 2021
Yes, I also visited the Drach Caves when I was a child and they were incredibly beautiful too! Breathtaking! PS. Sorry, I can understand French but I can't speak it :)