When it comes to outdoor adventures in Europe, Slovenia remains one of the continent’s hidden treasures. From vast underground cave systems to wild river canyons, this small country is packed with dramatic natural scenery. For visitors from the UK, it’s an ideal destination for adventure, nature, and unique geological wonders. In this guide, I will focus on the caves and canyons in Slovenia—what to expect, what to budget for, and how to make the most of your visit.
Why Explore the Caves and Canyons in Slovenia?
Slovenia’s karst landscape—characterised by porous limestone—has created more than 13,000 recorded caves, many open to the public. These underground marvels are filled with stalactites, stalagmites, underground rivers, and rare wildlife like the elusive olm. Alongside these subterranean wonders are dramatic canyons and gorges carved by glacial rivers, perfect for thrill-seekers.
I spent a significant amount of my childhood exploring the caves in the Périgord region of France, many with stalactites and stalagmites – these really are incredible sights to see, I never considered at the time that there were many more of these.
Top Caves in Slovenia: What to See and What It Costs
Postojna Cave – The Classic Choice
Postojna is Slovenia’s most famous cave and for good reason. This 24-kilometre-long cave system includes a 3.7 km electric train ride—the only one of its kind in the world. Visitors are treated to dramatic halls, spiky formations, and the world-famous proteus anguinus, also known as the “baby dragon” or human fish.
Highlights:
- Underground train experience
- The Concert Hall and Brilliant Passage
- Live olm display
Price:
- Adults: €32.90
- Children (6–15): €19.50
- Combo ticket with Predjama Castle: €46.50 (adult)
There is also a lower rate for students and children up to five-years-old only pay 1 euro.
Top tip: Dress warmly—even in summer, temperatures stay around 10°C. Buy tickets online to avoid queues.
Škocjan Caves – The UNESCO Wonder
A dramatic and less-commercialised alternative to Postojna, Škocjan features Europe’s largest underground canyon. You’ll cross suspension bridges, hear the roaring Reka River below, and walk through cathedral-sized chambers.
Highlights:
- Martel’s Chamber (one of the largest underground spaces in Europe)
- Natural bridges and towering cave walls
- Less crowded than Postojna
Price:
- Adults: €22
- Children (6–17): €10
- Students and Seniors: €16
Top tip: The terrain can be uneven, so good walking shoes are essential. Photography is not allowed inside. Purchase tickets in advance during peek holiday periods as they do sell out.
Križna Cave – For True Explorers
This semi-wild cave is a top pick for those seeking an authentic, less touristy experience. You’ll take a guided walk followed by a rubber boat ride over 13 underground lakes with crystal-clear water.
Highlights:
- Boat tour through lakes
- Preserved prehistoric bear bones
- No artificial lighting—tours use head torches
Price:
- Short tour (1 hour): €12 adults / €8 children
- Longer tours (up to 4 hours): €40+
- Advance booking required
Top tip: Not suitable for very young children or those with mobility issues. Bring a warm layer and expect to get slightly damp. Rubber boots and a flashlight are provided.
Breathtaking Canyons in Slovenia
Soča Valley – Adrenaline and Beauty
The emerald-green Soča River carves through limestone canyons, creating perfect conditions for white-water rafting, kayaking and canyoning. The Bovec area is the hub for guided canyoning trips, with tours catering to all skill levels.
Activities:
- Canyoning tours from €65–€90 per person
- Ziplining, kayaking, and rafting options available
- Equipment provided by local guides
Top tip: Book in advance during summer, and check that your tour includes insurance and qualified guides.
Grmečica Canyon – Hidden Adventure
Tucked away near Bohinj, this narrow canyon offers a mix of gentle abseils, natural water slides and plunge pools. It’s great for beginners and families, with fewer crowds than the Soča Valley.
Canyoning tours:
- Prices from €80
- Duration: 2–3 hours
- Minimum age typically 10+
Top tip: Combine your visit with a day at Lake Bohinj or nearby waterfalls for a full day of nature and relaxation.
Getting There from the UK
Flights:
- Direct flights from London, Manchester and Bristol to Ljubljana (2–2.5 hours)
- Budget airlines often offer return tickets for under £100 if booked early
Getting Around:
- Car hire from Ljubljana starts at around €30 per day
- Caves and canyons are spread across the country but all within a 2-hour drive
Public Transport:
- Trains and buses are available but less flexible than driving—ideal if you’re sticking to major attractions like Postojna
What to Pack
- Sturdy shoes or boots with grip
- Waterproof jacket and layers (even in summer)
- Swimwear and towel for canyoning
- Daypack with snacks, water and a power bank
- Camera or waterproof GoPro for canyoning photos
- Warm jumper for cave temperatures of 8–10°C
When to Go
- May–September: Ideal for canyoning and outdoor adventures
- July–August: Peak tourist season; book ahead and expect higher prices
- April & October: Quieter but still good for caves (less so for water activities)
Final Thoughts
Whether you’re marvelling at underground palaces of stalactites or leaping into crystal-clear canyon pools, the caves and canyons in Slovenia offer a perfect mix of nature, adventure, and awe-inspiring beauty. It’s an easy and affordable getaway from the UK that feels a world away from the usual tourist trail. Pack your sense of wonder—and don’t forget your waterproofs!
