20 sites · down to 287 m · 11 suitable for an intro team
Cave diving in Croatia
- Sites20
- Max depth287 m
- Water temperature5–27 °C
- Dive centres7
Diving and fills
Dive here with
Fills nearby
- Fill stationDiving Center Pongo (Primošten)Air, nitrox (30–36%), oxygen and helium (ask); stage cylinders and 3-litre rebreather cylindersRoute ↗
- Fill stationDiving Center B-24 (Komiža, Vis)Air, nitrox, trimix, O₂; booster (Dräger) to 300 barRoute ↗
- Fill stationDive Center Krk (Kornić)Air and nitrox (to 40 % €8, to 100 % €14 per fill, 2026); air in your own cylinder only with a valid inspectionRoute ↗
Why come here
Croatia has two sides. Along the coast and on the islands, from Premuda to Biševo, you dive sea caves and tunnels with daylight, often from open water, and near Zadar there are submarine springs (vrulje) with kilometres of cave, where cold spring water of ~9.5 °C lies over warm seawater of ~21 °C. Inland, around Knin, deep karst springs such as the Cetina and the Una rise from the Dinaric limestone, with water of 5–11 °C all year.
Those springs are protected and often drinking-water sources: no operator offers recreational dives there, so plan them as an expedition and get permission first; divers were fined at the Cetina in 2009. At sea you dive through a registered dive centre or with your own permit from the harbour master, with a buoy or dive flag, and in Kornati National Park only with one of the contracted centres. No fill station was found around Knin: bring your gas from the coast.
Don't miss
- Katedrala (Premuda): a system of connected caves with a dome-shaped hall where sunlight falls through holes in the porous ceiling, with no current and visibility averaging ~15 m.
- Špilja Lučice (Brač): you swim into a huge dome with overgrown walls and a dry section with stalactites high in the ceiling, and once your eyes adjust you can see without a torch.
- Vrulja (Brela): fresh water flows out of a submarine spring, rises to the surface and turns the sea azure; per HGSS (2014) the world's deepest active submarine spring.
- Vrulja Modrič: an anchialine cave of almost 3 km with speleothems and many side passages, where fresh spring water lies over seawater; a full cave dive with 2–8 m visibility, clay and strict line discipline.
On a rest day
- Knin Fortress: The fortress on the steep Spas hill, ~100 m above Knin and close to the source of the Krka, overlooks the route from Dalmatia inland.
- Krka National Park: Walk past the travertine waterfalls of the Krka, such as the 17 falls of Skradinski buk and Roški slap, and take a boat to the monastery island of Visovac.
- Cathedral of St James, Šibenik: A cathedral built entirely of stone between 1431 and 1535, with a frieze of dozens of sculpted faces.
All 20 sites
1 closed not shown ·
| Site | Max depth | Type | Certification |
|---|---|---|---|
| Big Cave / Cathedral (Cres)Backmount · Open water / no overhead | – | Backmount | Open water / no overhead |
| Blue Hole (Cres)Not known yet · Cavern | 20 m | Not known yet | Cavern |
| Geierfels and Bat Cave (Plavnik)Not known yet · Cavern | – | Not known yet | Cavern |
| Izvor Cetine (Glavaš)Permission neededBackmount · Full cave | 115 m | Backmount | Full cave |
| Izvor KrnjezeNot known yet · Full cave | 106 m | Not known yet | Full cave |
| Izvor KupePermission neededNot known yet · Full cave | 154 m | Not known yet | Full cave |
| Jezero Sinjac (Gorske oči)Not known yet · Full cave | 208 m | Not known yet | Full cave |
| Katedrala (Premuda)Backmount · Open water / no overhead | 30 m | Backmount | Open water / no overhead |
| Medvidina špilja (Biševo)Backmount · Open water / no overhead | 30 m | Backmount | Open water / no overhead |
| Nikolajova jeskyně (Sveta Marina)Backmount · Cavern | 35 m | Backmount | Cavern |
| Prvić TunnelBackmount · Open water / no overhead | 12 m | Backmount | Open water / no overhead |
| Špilja Brbišćica (Dugi otok)Backmount · Open water / no overhead | 30 m | Backmount | Open water / no overhead |
| Špilja Lučice (Brač)Backmount · Open water / no overhead | 35 m | Backmount | Open water / no overhead |
| Špilja PoganicaSidemount · Full cave | 60 m | Sidemount | Full cave |
| Vrbnik Cave (Krk)Backmount · Cavern | 13 m | Backmount | Cavern |
| Vrelo UnePermission neededEntry or dive feeBackmount · Full cave | 248 m | Backmount | Full cave |
| Vrulja (Brela)Backmount · Cavern | 161 m | Backmount | Cavern |
| Vrulja ModričPermission neededNot known yet · Full cave | 36 m | Not known yet | Full cave |
| Vrulja ZečicaPermission neededNot known yet · Full cave | 49 m | Not known yet | Full cave |
Certification requirements, configurations and trimix depths are estimates for planning. Always check them locally and dive within your training.
Map
Dive centres and fill stations
7 dive centres, fill stations and instructors
Dive centre
Diving Center Pongo (Primošten)
Raduča ul. 11, 22202 Primošten
- Air, nitrox, oxygen and helium
- Sidemount, Trimix · TDI
Fill station
Diving Center B-24 (Komiža, Vis)
Obala Pape Aleksandra III 8, 21485 Komiža, Vis
- Air, nitrox, trimix, O₂
- CCR (ISC Megalodon and Pathfinder, €80), absorbent and 3 l cylinders
Dive centre
Dive Center Krk (Kornić)
Dunat 50, 51517 Kornić, Krk
- Air and nitrox
- Vrbnik Cave (Krk), Big Cave / Cathedral (Cres), Prvić Tunnel, Blue Hole (Cres)Geierfels and Bat Cave (Plavnik)
- Full equipment and 7–15 l cylinders (mostly 12 l steel, DIN)
Dive centre
Just Dive Croatia (Biograd na Moru)
Biograd na Moru
- Air and nitrox to 200 bar
- Sidemount, Trimix
Fill station
Kornati Diving Center (Sali, Dugi otok)
Zaglav 15, 23281 Sali, Dugi otok
- Air, nitrox, trimix, O₂, helium
Dive centre
Kron Diving (Rab)
Kampor 413a, 51280 Rab
- Air, nitrox, trimix, O₂, argon
- CCR · SSI
- Drysuits and cylinders
Fill station
Triton Diving (Vrsar)
Camping Orsera, Ul. Sv. Martina 2/1, 52450 Vrsar
- Air, nitrox up to 80% and oxygen
Order: partners first, clearly marked as partner; then dive centres by distance from Knin and independent instructors by name. Not a recommendation: check what they offer yourself.
On this list, or should you be? Get a free partner card →Where to stay
Find a place near Knin, Vrlika, Split, Zadar, Mali Lošinj, Komiža (Vis), Rijeka
Villages that work well as a base for the caves in this region. Find a place for your team:
- KninBooking.com ↗
- VrlikaBooking.com ↗
- SplitBooking.com ↗
- ZadarBooking.com ↗
- Mali LošinjBooking.com ↗
- Komiža (Vis)Booking.com ↗
- RijekaBooking.com ↗
The links to Booking.com are affiliate links: if you book through one, DiveTripPlanner earns a small commission. You pay the same.
Practical info: rules, fills and emergency numbers
Access and rules
- Permit: in Croatia any entry into a cave or pit needs a permit from the Ministry of Environmental Protection and Green Transition; local speleologists get yearly research permits. Croatian speleologists have carried out several searches for unannounced cave divers who did not come back from the flooded passages (Croatian Speleological Federation, Nov 2026).
Gas and fills
- Gas and CCR: trimix and O₂ at Kron Diving (Rab; rEvo training centre, full rebreather support), Kornati Diving Center (Sali, Dugi otok; booster), B-24 (Komiža, Vis; up to 300 bar, rental CCR ISC Megalodon/Pathfinder €80) and Just Dive (Biograd; O₂ and helium per 100 l). No fill station was found around Knin/Vrlika — bring your gas from the coast. In Split, LUK Technical Diving (Andrija Lukenda, +385 98 990 3231) teaches JJ-CCR and trimix; ask about fills.
Water and season
- Water: springs 5–11 °C year-round (Kupa 5–7 °C, Cetina ~8 °C, Una avg 9.5 °C). Sea in the north (Istria) ~9 °C in April to ~20 °C in September; around Brač 17–27 °C. In vrulje cold fresh water (~9.5 °C) meets warm seawater (~21 °C).
Safety
- Accident: call 112. HGSS (mountain rescue) has its own cave-diving rescue team. Chambers: KBC Rijeka, Centre for Underwater and Hyperbaric Medicine, Tome Strižića 3, Rijeka (Sušak), +385 51 407 435 — team reachable 24/7 (sessions Mon–Fri 8:00–16:00, weekends emergencies only). OXY Pula, Santoriova 24a, +385 52 215 663 (office Mon–Fri 7:30–15:30; 24 h numbers +385 98 219 225 / +385 98 381 693 per a 2022 list). Split: chamber of the Navy's Institute of Maritime Medicine (IPM HRM), Šoltanska 1, +385 21 354 511. Dubrovnik: OXY, Dr. Roka Mišetića 2, +385 20 431 687 (24 h: +385 98 381 685, 2022 list). Zagreb: OXY, Makarska ulica 5. OXY is contracted by the Croatian health fund HZZO. DAN Europe +39 06 4211 5685.
Good to know
- Sea diving: through a registered dive centre or diving club. Independent divers need an 'odobrenje za individualno ronjenje' from a harbour master's office (lučka kapetanija Pula, Rijeka, Senj, Zadar, Šibenik, Split, Ploče or Dubrovnik): per the ministry's page 2,400 kuna (~€320), valid one year — check the current euro fee. Mark your dive with an orange/red buoy (≥30 cm) or a dive flag; separate bans apply at wrecks and archaeological zones.
- Inland springs: the deep springs are protected (Izvor Cetine natural monument since 1972, Vrelo Une since 1968, Izvor Kupe in Risnjak NP) and often drinking-water sources. Swimming is banned at the Cetina spring (since 2022, 400 m downstream) and at Vrelo Une (entry €3). Divers were fined for unauthorised diving at the Cetina in 2009. No operator offers recreational spring dives: plan it as an expedition and get permission first (municipality, Hrvatske vode, the county nature-protection body — Natura Jadera for the Una — or the national park).
- Vrulje (submarine springs): Modrič (~2.9 km) and Zečica (1.2 km) near Rovanjska were explored by foreign teams with CCR and scooters, under a Croatian diving permit and with local cave divers; halocline, clay and 2–8 m visibility.
- Kornati NP: independent diving is banned; only with one of the 7 contracted centres (2026), in 9 zones, max -40 m, no night dives (19:00–7:00). Just Dive (Biograd) charges a €38 park surcharge.
- Bases: Knin or Vrlika for the inland springs; an island base for the sea caves (Komiža for Biševo, Split for Šolta/Brač, Mali Lošinj or Zadar for Premuda and Dugi otok) — the islands are reached by ferry. In the Kvarner, caverns and tunnels are plentiful around Krk, Cres, Plavnik and Prvić; Dive Center Krk (Kornić) takes guided boat trips there.
News
News articles that mention one of the caves in this region, collected automatically and not checked by us.
Access and rules change: check what applies locally right before your trip. Source: GDELT Project and the news feeds of diving magazines.
Searched automatically, last on 13 Nov 2026.
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