By Kim Irvine in Days Out In Europe — 24 Jul 2026

🇸🇮 Postojna Cave, Slovenia

A spectacular underground world unlike anywhere else. We travelled deep into Postojna Cave by electric train before exploring vast limestone caverns on foot. If you’re planning a visit, here’s what to expect, what it costs, and a few tips we wish we’d known before arriving.

One of Europe’s most remarkable cave systems, featuring an unforgettable underground train ride and spectacular limestone formations.

📍 Location

Postojna, Slovenia

📍 Distance from Ljubljana

Postojna Cave is around 50 km (31 miles) southwest of Ljubljana and takes approximately 40 minutes by car, making it an easy half-day or full-day trip from the Slovenian capital. If you also plan to visit Predjama Castle, allow a full day.

⭐ At a glance

🚂 Underground electric train journey
🚶 Guided walking tour through spectacular caves
❄️ Constant temperature of around 10°C
⏱️ Allow 2–3 hours
🚐 Motorhome parking nearby

📖 A little history

Postojna Cave is Slovenia’s most famous natural attraction and one of the largest show caves in Europe. Over 24 kilometres of passages have been discovered, with around 5 kilometres included on the visitor tour. Millions of people have visited since tourism began here more than 200 years ago.

🚶 What we did

We hadn’t booked our tickets before arriving and, although we were able to get on a tour, the next available departure wasn’t for quite a while. We spent the time looking around the visitor area before boarding the famous underground train.

The train takes you deep into the cave before you continue on foot with a guided tour through enormous caverns filled with incredible stalactites and stalagmites. The scale of the cave is difficult to appreciate until you’re inside.

🚐 Motorhome information

There is a dedicated motorhome stellplatz next to the visitor centre. We considered staying there, but when we arrived there were no other motorhomes there and it felt rather isolated, so we decided not to stay and continued to our campsite instead.

Parking for day visitors is available close to the entrance.

🚴 Walking & cycling

The cave visit itself involves a moderate amount of walking after the train ride.

⏱️ Time to allow

Allow 2–3 hours for the cave tour.

If you’re planning to visit Predjama Castle on the same day, allow a full day.

💷 Ticket prices

At the time of writing:

Postojna Cave: €34.90 per adult
Predjama Castle: €24.00 per adult
Combined Cave & Castle ticket: €49.90 per adult

Buying the combined ticket is the best value if you intend to visit both attractions.

👍 Highlights

The unique underground electric train.
Huge cave chambers and stunning rock formations.
Excellent guided tour.

👎 Things to know

Book your tickets online in advance during busy periods if possible. We bought our tickets when we arrived but had quite a wait for the next available tour.
The cave stays at around 10°C, even in summer, so take a warm top.
Wear comfortable walking shoes.

⭐ Our rating

⭐⭐⭐⭐⭐ 9/10

We really enjoyed our visit to Postojna Cave. The underground train, the sheer size of the caverns and the incredible rock formations made it a memorable experience. Although it is one of Slovenia’s more expensive attractions, we felt it was well worth the admission price and would definitely recommend it.