Slovenia

Map

Not to be missed

• Divje jezero →

  The 'Wild Lake' near Idrija is a protected natural monument and a deep spring to 160 m, only for experienced trimix divers.

• Veliko okence (Retovje) →

  One of the Retovje springs near Vrhnika: down to 25 m and easy to combine with the walk past the springs.

• Izvir Krupe →

  The Krupa spring near Semič is a natural monument and, at a maximum of 7 m, a shallow full cave dive.

• Bilpa →

  A powerful karst spring near Kočevje, at its best after a dry spell.

• Luknja pri Plavah →

  A cavern dive to 24 m and so the entry point for divers without a full cave certification (yet).

Regions

• SloveniaA handful of karst springs — the deep Divje jezero near Idrija (-160 m), the Retovje springs of the Ljubljanica near Vrhnika and the Bilpa on the Kolpa — plus research caves such as Planinska jama; under the Slovenian diving act foreigners may only dive them after notifying the police and together with a qualified Slovenian diver.8 caves · down to 160 m

Good to know

• In Slovenia, cave diving counts as 'technical diving'. As a foreigner you notify the local police of place and time beforehand, carry accident and life insurance and proof of training, and dive together with a qualified Slovenian diver. Check with a Slovenian dive centre or the SPZ whether this still applies.
• Compressed air is allowed to -40 m; deeper you dive on trimix.
• Caves are state property and protected: there are freely accessible, controlled and closed caves. Motorised vehicles are banned; electric scooters are only allowed for sump research.
• Diving can be restricted or banned in nature- and water-protection areas. For sites in Triglav National Park you ask the park for consent; Divje jezero and the Krupa are natural monuments.
• The water is cold all year, roughly 6 to 10 °C: dive in a drysuit. Slovenian cave divers dive year-round.

Tips for safe and enjoyable diving

• After heavy rain, springs such as the Bilpa and Divje jezero flow hard. Plan those dives after a dry spell.
• Gas: Norik-sub in Ljubljana fills air, nitrox, O₂, trimix and heliox to 300 bar (Mon–Fri). Društvo Kisik in Bled has trimix and O₂ on request. Ask about sofnolime.
• Emergency: call 112. In a cave accident the cave rescue service JRS turns out. The nearest chamber is in Ljubljana; always call ahead.
• Ljubljana is a handy central base with a fill station. For individual sites you can also stay in Vrhnika, Idrija, Postojna, Kočevje or Semič.
• Rest day: visit Idrija (UNESCO Global Geopark), walk the circular route past the Retovje springs or visit Planinska jama.

Certification requirements, configurations and trimix depths are estimates for planning. Always check them locally and dive within your training.

News

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Searched automatically, last on 5 Oct 2026.