Postojna Cave

Postojna Cave at a Glance

Why Visit Postojna Cave

Postojna Cave combines a long karst system, an underground electric railway, large chambers, the Pivka River, and the olm vivarium. The page also connects the cave with Predjama Castle and the wider Karst region, making the visit more than a single underground viewpoint.

Overview

The guide describes Postojna as a cave system formed by the Pivka River, with a constant 8–10°C environment, a 3.5 km underground railway route, walking through large chambers, and a vivarium for the olm. Predjama Castle is linked by an underground passage that is not open to the public.

Best Things to Do in Postojna Cave

Postojna Cave (Postojnska jama) is the most visited cave in Europe and one of the world's most spectacular karst systems. The cave stretches over 24 km, making it the second-longest publicly accessible cave system in Europe (after Mammoth Cave, USA for total length). What sets Postojna apart from other show caves is the unique underground railway — visitors ride a small electric train 3.5 km into the heart of the cave, covering the distance in 15 minutes. The tour then continues on foot through vast chambers including the Great Hall (300 x 90 x 30 metres), the Petra Hall, and the exquisite White Hall with its pristine white stalactites.

Exploring Postojna Cave: Top Attractions & Hidden Gems

The cave was formed over millions of years by the Pivka River, which still flows through the lower passages. The temperature stays at a constant 8-10°C. The cave's most famous resident is the olm (Proteus anguinus), also known as the 'human fish' — a blind, pink amphibian that lives exclusively in the Dinaric Karst underground waters and can live to 100 years old. The Proteus vivarium at the cave entrance displays live olms in a recreated underground environment (included with cave entry).

Local Culture & Food in Postojna Cave

The Predjama Castle connection is another highlight — a 9 km underground passage connects the cave to Predjama Castle (not open to the public, but the story is fascinating). Postojna Cave was first described in the 17th century by Valvasor, opened to tourists in 1819 (when Archduke Ferdinand I visited), and the railway was installed in 1872 — the same year the first electric lighting was tested in a European cave. The cave hosts occasional concerts in the Great Hall (exceptional acoustics — the Vienna Philharmonic has performed here). The karst research centre at the cave entrance conducts ongoing speleobiology research. The cave's formations include extraordinary examples of stalactites, stalagmites, flowstones, helictites (gravity-defying formations), and cave pearls (€2-5 for a small souvenir at the gift shop).

🗓 Best Time to Visit

Open year-round (constant 8-10°C in the cave, so no season is bad). July-August is busiest with queues up to 45 minutes — book online and arrive early. May-June and September-October offer the best balance of manageable crowds and pleasant above-ground weather. November-March is quiet with fewer tours (check the schedule). Avoid visiting during heavy rain when the cave may flood lower passages (rare but possible Nov-Mar). The outdoor park and Proteus vivarium are best in summer.

🍽 Food & Drink

Postojna town has several restaurants (the cave complex has a self-service buffet that's acceptable for a quick meal but not memorable). Must-try dishes in the area include jota (€8-12), pršut (Karst ham, €6-9), and local trout from the Pivka River (€12-16). The Postojna region is known for its teran wine (€2-3 per glass). For a proper meal, skip the cave buffet and walk into Postojna town (15 min walk or 5 min drive). Restaurants: Gostilna Kraški Kras (mains €10-16, a 10-minute walk from the cave, good jota and grilled meats), Restaurant Jama (mains €8-14, near the cave entrance, decent Slovenian fare). For picnic supplies, the Mercator supermarket in Postojna town has everything.

🚗 How to Get to Postojna Cave by Bus, Car & Boat

By car: Postojna is on the A1 motorway, 45 km from Ljubljana (35 min). The cave has a large car park (free). By train: Postojna station is on the Ljubljana-Koper line (€5-8, 1 hour, 6 daily trains). The station is 2 km from the cave entrance — a 25-minute walk or €5-7 taxi. By bus: Direct buses from Ljubljana (€7-10, 1 hour, hourly). The bus stop is a 10-minute walk from the cave. By tour: Almost every Ljubljana tour agency runs half-day trips to Postojna (€45-65 including transport and entry, book 24h ahead). Combined tours with Predjama Castle (€55-75) are the most popular option.

🥘 Where to Eat in Postojna Cave: Authentic Local Cuisine

The cave complex has a self-service restaurant (mains €8-14, open during cave hours) — functional but not special. For better food, Gostilna Kraški Kras (Titov trg 1, Postojna, €10-16 mains, 10 min walk from the cave) is the best option — try the jota or grilled meats. Gostilna Jama (mains €8-14, just outside the cave entrance) is convenient with decent schnitzel and pizza. For a special meal, take the 9 km drive to Gostilna Špacapan in Škocjan (€12-22 mains, excellent Karst cuisine). The Postojna Central Market (Saturday mornings) has good local produce for a picnic. Pack a sandwich — the cave complex allows picnics in the outdoor park area (but not inside the cave).

🏨 Best Hotels Near Postojna Cave

There's no accommodation at the cave itself. Postojna town has Hotel Jama (€70-100/night, 5-min walk from the cave, clean and comfortable). For a unique experience, Hotel Grad Predjama (€80-120/night, in the castle's former stables, 9 km from the cave) offers castle accommodation. Guesthouse Pr' Štirbarok (€50-65/night) is a good budget option in Postojna town. For a rustic Karst experience, tourist farms in the area offer farm stays (€45-65/night with breakfast — ask at the Postojna tourist office). Most visitors day-trip from Ljubljana.

Common Mistakes

• Entering without a warm layer when the page gives a constant cave temperature of 8–10°C.
• Treating the railway as the whole visit and missing the walking route through the chambers and the olm vivarium.
• Assuming the Predjama underground passage is a public route when the page says it is not open to visitors.
• Planning around the busiest summer period without checking current tickets and visitor arrangements.
• Using flash or touching cave formations and displays where current instructions prohibit it.

Photography

The underground railway, Great Hall, cave formations, Pivka River context, and olm vivarium offer different subjects inside and around the cave. Follow the cave’s current photography, flash, and wildlife-display instructions. Civil Aviation Agency of Slovenia (caa.si) — check current registration and flight rules before flying drones.

Etiquette

A few low-impact habits fit this destination:

• Following guide, railway, and chamber instructions is essential cave etiquette.
• Keeping voices low in the underground halls is considerate.
• Asking before photographing staff or other visitors is common courtesy.
• Never touching formations or display surfaces helps protect the cave.
• Keeping food and drink to permitted areas is customary.

Frequently Asked Questions

Is Postojna Cave worth visiting?
Absolutely — it's one of Europe's most spectacular show caves and the underground train ride is a unique experience that no other cave in Europe offers at this scale. The formations are extraordinary, the olm is fascinating, and combining it with Predjama Castle makes for an excellent day trip. Budget 2-3 hours for the cave alone, 4-5 hours including Predjama Castle.

What is the temperature inside Postojna Cave?
The cave maintains a constant 8-10°C (46-50°F) year-round with high humidity (95%%). Wear a warm jacket or sweater regardless of the season. The walk covers about 2 km of pathways with some stairs — sturdy shoes are recommended. The underground train provides shelter from the temperature.

How do I get from Postojna Cave to Predjama Castle?
Predjama Castle is 9 km from Postojna Cave — a 15-minute drive. There is no direct public transport between the two. By taxi: €12-18 one way (plenty of taxis waiting at the cave). By bike: 9 km on a quiet country road (40 min). Many tour companies offer combined packages. If driving, it's a straightforward route through the karst landscape.

What is the olm (human fish) at Postojna Cave?
The olm (Proteus anguinus) is a blind, pale pink amphibian that lives exclusively in the underground waters of the Dinaric Karst. It can live for 100 years and survive without food for up to 10 years. The Proteus Vivarium at Postojna Cave has several live olms in a specially designed habitat. They're one of the cave's most famous attractions and a symbol of Slovenian natural heritage.

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