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One of the best things to do in Ljubljana is to take a day trip to the Postojna Cave Park. Start your day at Postojna cave, one of the largest underground caves in the world, displaying the finest collections of stalactites and stalagmites that have formed over millions of years.
Next, we go on to Predjama Castle, the largest cave castle in the world. Step into the rich folklore of Slovenia and see its medieval architecture, which has been said to have inspired a few famous medieval writers.
I learnt so many fascinating stories and saw so much on this trip that left me in awe at every turn. With both places being so close to Ljubljana, it makes perfect sense to add this to your itinerary and see what makes these both so renowned for being some of Slovenia’s most beautiful places to visit.
Getting to Postojna Cave from Ljubljana
By car
It takes 37-40 minutes from central Ljubljana to Postojna Cave by car driving on the A1 freeway. There is a huge parking space on site, and it costs €6 for a full day.
By train
It takes, on average, 1 hour and 10 minutes from Ljubljana to Postojna by train, and tickets cost €6.20 (concessions available). From Postojna Train Station, you’ll need to walk 28 minutes to the cave. You can use this route.
By bus
Buses run most days from Ljubljana Bus Station to Postojna. They are more frequent during the summer, and the duration averages around 1 hour. From the bus depot, you’ll need to walk 20 minutes to the cave following this route.
Check out the latest bus schedule.
By tour
From Bled or Ljubljana, you can take a guided tour of Postojna Cave and Predjama Castle. It provides entry to the attractions and hotel drop-offs, so you don’t have to worry about a thing!
When to visit Postojna Cave and Predjama Castle
Postojna Cave and Predjama Castle are open all year round, with extended opening hours during the summer. View more details on the opening hours here.
You must pre-book a tour time slot to explore Postojna Cave and arrive at least 10-15 minutes early. However, Predjama Castle can be self-explored.
Note: Summer will be the busiest time to visit both, with many tourists coming from Lake Bled and Ljubljana.
Ticket information
The cost for Postojna Cave and Predjama Castle together is €41.90. However, your experience can be altered with other attractions available at an added price.
You can also opt for a single ticket to either attraction. Updated ticket prices for all attractions can be found here.
Postojna Cave
Postojna Cave is truly one of the most beautiful places in Slovenia. During your time at the Cave, you’ll explore around 5km of the 24km stretch of underground caverns, stalactites and stalagmites that have been formed for over 3 million years.
Huge Warning! The cave can hit temperatures as low as 10°C. So I advise you to wrap up as warm as possible before entering.
Exploring the cave
When you arrive at the entrance, you’ll be separated into language-specific groups. (Will differ if you are part of a tour)
To enter the main part of the cave, you’ll need to ride the thrilling electric train. The train takes you through 3.7km of underground tunnels past many stalactites and stalagmites. It is very scenic! Don’t worry for non-thrill seekers – it doesn’t go more than 10 km/h and lasts 10 minutes.
Also, if you are tall, just be wary of the lower sections. Luckily, that didn’t apply to me.
The tour
Once you arrive in the main cave section, it is time to begin the 1-1.5 hour walk around the stunning rock formations of Postojna Cave.
Your tour guides will stop at designated stations and provide information on the cave, giving you plenty of time for photo opportunities.
What you’ll see
As you are guided around the cave, you’ll be introduced to the many different types of incredible rock formations that have formed there for millions of years.
The stalactites and stalagmites were formed through cool water drips that, over time, left behind tiny bits of calcite hanging from the ceiling and up from the ground that eventually formed the rock formations we see today.
From their resemblance, these cool shapes have gained the name ‘curtains and draperies’.
Be sure to look out for the five-metre-tall white stalagmite called Brilliant next to a giant column. This is the symbol of Postojna Cave and the Slovenian Karst. I’m sure your tour guide will point it out!
Wildlife in Postojna Cave
The Postojna Cave is home to a variety of different species, from bats to unusual insects, you name it.
Its most famous creature is olm, the cave’s very own salamander. These have famously gained their nickname ‘baby dragons’ for their slender-like appearance.
Olms are fully blind and have adapted to the conditions of the cave’s pure darkness. You will see a few in a glass box at the end of the tour!
Fun fact: It can live up to 100 years and only needs to eat a few times a decade.
It’s not the kind of +1 you’d want to invite to a buffet!
Extra Postojna Cave attractions
Vivarium
The Vivarium is just next to the Postojna Cave entrance, which is split into two parts.
The first part displays the old research lab used to perform scientific research on the cave. The second part is an exhibition where you’ll learn all you need to know about the 150 wildlife species living inside the cave, including a closer look into the baby dragon ‘olm’ itself.
It is super fascinating and well worth the visit for an enhanced experience during your time here!
Expo Cave Karst
This little attraction is a brilliant way to dive deeper into how the cave’s Karst formations were formed, including insights into how the cave has developed as a tourist attraction.
As you walk around, you’ll notice some signatures on the cave walls. Visitors used to mark their visit to the cave through a signature. You’ll see some even dating back to the 1820s!
This is no longer permitted! Sorry Banksy, but you are banned from entering.
The main part of the exhibition will walk you through a detailed series of events and coincidences during the creation of the cave through interactive exhibits and displays.
This proved to be helpful; as someone who has, at times, questionable listening skills, I was able to learn a few things that I unfortunately missed during my tour.
The Expo Cave Karst also includes free access to the exhibitions Life Within a Billion Years and Butterflies of the World.
Getting from Postojna Cave to Predjama Castle
To get from Postojna Cave to Predjama, you have a few options;
Car – It is a 14-minute drive to Predjama Castle from Postojna Cave. Parking is right next to the castle and costs €3 an hour.
Taxi – Taxis can be booked via the ticket office of Postojna Cave. You can expect to pay around €30-€40 for a return.
Shuttle bus *subject to timescale* – Usually, during the summer (July to August), a shuttle bus runs every hour, taking you from Postojna Cave to Predjama Castle (including the other way). However, in some years, it can run from June to November.
Check out the current timescale for this year. The shuttle bus cost €1.50 from Postojna Cave for both ways. (It used to be free)
If you have booked via a tour, then brilliant, transport will be all sorted for you!
Predjama Castle
Predjama Castle is one of the most fascinating monuments in Slovenia. Built-in the 13th century, this medieval fortress is set in the mouth of a cave, hanging on by a mere cliff edge.
The castle has a long and rich history, notably for being the home of several noble families in Slovenia for centuries.
Exploring the castle
When you arrive at Predjama Castle, free audio guides will be handed to you, which can be scanned at numbered stations in the castle to learn more about its fascinating history.
Learning about the Slovenian folklore
As you walk inside, you’ll quickly feel immersed in what feels like a fairytale, and that is for a good reason. There is a lot more folklore to tell the tale! You’ll soon learn about it.
Its most famous resident, the knight Erazem Lueger, lived in the castle and became a legendary Slovenian folklore hero.
Erazem was Slovenia’s very own ‘Robin Hood, who was notorious for fighting for the lives of the poor and stealing from the rich. His most famous tale was when he fought off resistance from the Habsburgs.
What to expect at the castle
The castle itself is like a TARDIS. Although it looks small from its exterior, there are so many little unique things to explore inside that build up your intrigue.
Some of the highlights include The Castle Great Hall, which was used for feasts for the kings! The bell at the top, that you must ring and make a wish. Or the armoury that stored all the weapons, armour and necessities needed to help defend the castle from sieges.
A notable part of the castle is the cave and the secret tunnel that can be accessed behind the castle at the very top.
Erazem and many others used this to escape the castle if they needed to gather supplies during a siege or, in some cases, avoid execution.
Under the castle, there is also an underground cave that spans over 14km long. However, tourists can only see around 700m of it. This requires a separate ticket and can be bought from the ticket office. Tickets cost €12.50.
Note: The cave is only open from May to September. It is home to a colony of bats during Winter that use it to hibernate.
Final thoughts on a trip to Postojna Cave and Predjama Castle
Well, there you have it! Both these attractions make for a perfect trip away from the bustling capital of Ljubljana.
Featuring an array of stunning natural formations and impressive folklore, Postojna Caves and Predjama Castle will provide you with a unique perspective for your Slovenia travels.
With just a short journey by road or rail away from Ljubljana and other major cities, what’s not to be missed?
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