The Cave Under the Volcano: Katla Ice Cave

The Traveler's Panel · checked 13 August 2026

Changing information. Prices, permits, seasons and road access change, sometimes at short notice. Everything here is a starting point for your own confirmation — not a quote, and not a guarantee. Verify with the operator and the relevant official body before you book.

Getting there — Keflavík (KEF) → Route 1 → Vík í Mýrdal

1. Fly to Keflavík and drive Route 1 east to Vík í Mýrdal, about 187 km from Reykjavík. Scheduled south-coast buses also serve Vík, and meeting the tour in town is the lowest-impact option.
2. All access to the cave is by licensed super jeep from Vík across the outwash plain east of town. There is no road to the glacier and no lawful self-drive route; do not attempt one.
3. Meeting points are in Vík itself — the Vík Inn lobby, the Icewear Magasin car park and Austurvegur, depending on operator. Arrive about twenty minutes early.
4. Before travelling, check the Icelandic Meteorological Office for Katla's status and for jökulhlaup notices. The Office has twice in recent years advised staying off Kötlujökull during seismic swarms — most explicitly on 30 June 2023.
5. In winter treat the drive as the main hazard of the day and check road.is and vedur.is before leaving Reykjavík. The south coast changes weather faster than the forecast interval.
6. Book ahead year-round. Summer departures fill and winter ones are weather-limited.

Indicative costs — verify before booking

What to pack

• Waterproof shell and warm mid-layers. The cave mouth funnels wind in July as well as January.
• Wool or synthetic base layers. No cotton next to the skin.
• Sturdy waterproof boots stiff enough to take a strap-on crampon; the crampons are provided.
• Gloves, hat and eye protection — glare off ice and wind-driven grit off the black sand.
• Water and a snack. The jeep crossing is longer and rougher than the tour length suggests.

Where to stay

Vík í Mýrdal is the obvious base and the only sensible one: it is the meeting point for every operator running this cave, it has hotels, guesthouses, fuel and food, and it puts Reynisfjara and Dyrhólaey ten minutes away. Staying in Vík rather than driving out from Reykjavík also means you can take a morning departure, which is the better light inside the ice, and can absorb a cancellation without losing a day. Further east, Kirkjubæjarklaustur is about seventy kilometres on and works if you are continuing toward Skaftafell and Jökulsárlón. Note that Vík sits below Mýrdalsjökull and inside the Katla civil-protection area; alerting is by SMS to phones in the affected zone.

Safety & responsible travel

• Do not go onto Kötlujökull without a licensed guide, and do not treat a summer booking as evidence of safety. There is no Icelandic regulation governing ice-cave tours outside Vatnajökull National Park, and the Tourist Board has said it lacks the power to make one.
• Check the Met Office before you go, not the booking platform. Seismic swarms at Katla have produced explicit advice to stay off this glacier, most recently in June 2023.
• Understand the flood hazard. Kötlujökull drains into Múlakvísl, which took out the Ring Road bridge in July 2011 without an eruption. Do not linger in river channels on the sandur.
• Stay inside the roped line and accept cancellations. In the absence of regulation, the operator's willingness to turn back is the only real safeguard in the system.
• Do not repeat 'the ash insulates the glacier.' Thin tephra accelerates melt; Mýrdalsjökull's worst measured mass-balance year is 2010, the year ash fell on it.
• Accessibility: the walk from the drop-off is short and mostly flat, but the surface is volcanic gravel and ice and the jeep crossing is rough. Ask operators directly rather than relying on the word 'accessible' in marketing copy.

Nearby, and quieter

Reynisfjara and its basalt stacks are minutes west of Vík, with sneaker waves that have killed repeatedly — stay well back from the water. Dyrhólaey's arch and puffin cliffs sit alongside. Mýrdalssandur east of town is the outwash plain the 1918 jökulhlaup rebuilt, and Hafursey rises out of it beside the route to the glacier. Þakgil, up a gravel track north-east of Vík, is the quiet counterweight to the cave. Sólheimajökull, half an hour west, is the same ice cap's other famous outlet — and as of the Met Office's notice of 22 July 2026 its margin carried a hazard warning and operators had suspended trips. The winter blue caves in Vatnajökull National Park are a separate trip, two and a half hours east, under a separate and much stricter regime.

Getting there, in order

• 1Keflavík (KEF)
• ↓
• 2Route 1
• ↓
• 3Vík í Mýrdal

Each leg is a separate booking and a separate chance to be weathered out. Build spare days into the chain, not onto the end of it.

Where it is

Iceland · 63.6300°N 18.8700°W · Open in Google Maps · OpenStreetMap

Key locations

• Vík í Mýrdal — the town 187 km from Reykjavík where every super-jeep tour meets
  63.4194°N 19.0097°W
• Mýrdalsjökull — the ice cap Kötlujökull leaves through the caldera breach
  63.6432°N 19.1737°W
• Katla — the caldera under the ice, at least 21 eruptions in 1,100 years
  63.6315°N 19.0623°W
• Sandfell — the northern mountain of the gap the glacier tongue spreads through
  63.6524°N 18.8201°W
• Hafursey — the southern mountain of the same gap, crossed on the jeep run
  63.5229°N 18.7771°W
• Múlakvísl — Kötlujökull's meltwater river; the 2011 flood took the Ring Road bridge
  63.4059°N 18.8886°W

Coordinates are for orientation and are accurate to roughly the width of the feature named, not to a doorway. Several of these points are inside protected areas or need a permit, a guide or a boat — read the access notes above before you plan a route to any of them.

Sources & further reading — checked 13 August 2026

1. Icelandic Meteorological Office — Katla volcano. The ice-filled 9 × 14 km caldera with the central volcano rising to 1,500 m; at least 21 eruptions in the past 1,100 years; an average historical repose of about 50 years; the last ice-penetrating eruption in 1918; the Eldgjá event of about 939 CE at roughly 20 km³; and jökulhlaups as the characteristic accompanying hazard
2. Icelandic Meteorological Office — 100 years since Katla erupted. That the 1918–2018 gap is the longest since a Katla eruption, and — importantly — the Office's own framing: it does not say 'overdue', it says the next eruption is expected to be preceded by detectable precursors including increased seismicity, changed seismic patterns, inflation and changes in gas flux
3. Icelandic Meteorological Office — Earthquakes in Mýrdalsjökull (30 June 2023). Ninety-five earthquakes by 06:30, eight above M3 and a largest of M4.4; the largest activity since autumn 2016; attribution mainly to elevated geothermal processes with magma not ruled out; high conductivity in Múlakvísl and gas at Láguhvolar; and the explicit advice to avoid where Múlakvísl leaves Kötlujökull and to stay off Kötlujökull itself
4. Veðurstofa Íslands — Kröftug jarðskjálftahrina í Mýrdalsjökli (20 October 2025). The swarm beginning about 10:30 on 20 October 2025, several events above M3 and a largest of M4.4; the assessment that it was developing as the May and June 2023 swarms had; no change in conductivity to indicate an impending jökulhlaup; and the description of May 2023's largest event as M4.8
5. Iceland Review — Three Earthquakes Over M4 at Katla Volcano (4 May 2023). The 4 May 2023 swarm with three events above M4 and a largest reported at M4.5 — the figure that conflicts with the Met Office's later M4.8 — the aviation colour code raised to yellow, and confirmation that no flood began
6. Icelandic Meteorological Office — On the micro-earthquake activity at Mýrdalsjökull (29 July 2016). Over 100 shallow caldera earthquakes from 1 June 2016, about four times the monthly average, two M3.2 events on 26 July, three small Múlakvísl floods, and the assessment that this was typical summertime unrest with no deformation or tremor indicating magma movement
7. Icelandic Meteorological Office — Seismic swarm at Katla (30 September 2016). The 29–30 September 2016 swarm with several events around M3 or larger, no tremor, and the aviation colour code raised from green to yellow
8. Icelandic Meteorological Office — A jökulhlaup from Mýrdalsjökull into the rivers Leirá Syðri and Skálm (July 2025). The 8–11 July 2025 outburst from cauldrons 13 and 14 south of Austmannsbunga; nearly 100 accompanying earthquakes with a largest of M2.7 on 10 July; the sulphur smell near Skálm and the gas-pollution warning; and confirmation that no eruption occurred
9. Icelandic Meteorological Office — Increased hazard at the margin of Sólheimajökull (22 July 2026). The thinned and unstable ice ridge, the new eastern lagoon, the rockfall hazard along most of the access path, and the suspension of tours by operators — used here for the neighbouring outlet of the same ice cap
10. Veðurstofa Íslands — Jöklar á Íslandi halda áfram að rýrna (29 June 2026). The 2024–25 round at about 130 sites; the finding that the slower phase of 2012–2020 has ended and mass loss has returned to 1995–2011 rates; unusual autumn and winter warmth and one of the warmest summers on record; and that change is greatest on the larger outlets of Vatnajökull, Langjökull and Mýrdalsjökull
11. Jökull 75 (2026) — Hrafnhildur Hannesdóttir, Jökulsporðamælingar 2024–2025. The Iceland Glaciological Society's front-variation data report: Kötlujökull −30 m, observer Jóhannes Marteinn Jóhannesson; Sólheimajökull western tongue −93 m; Öldufellsjökull −75 m; Sléttjökull −35 m; and the summary that the majority of glacier termini are retreating
12. Jökull 73 (2023) — Geodetic mass balance of Mýrdalsjökull ice cap, 1999–2021. Mýrdalsjökull at 520 km² in 2019, about 140 km³ and a mean thickness near 230 m, with ice up to about 750 m over the roughly 100 km² caldera and a high point of 1,493 m at Goðabunga; mass balance of −1.23 ± 0.10 m w.e. a⁻¹ for 1999–2021 across sub-periods of −1.83, −1.45, −0.64 and −0.41; Kötlujökull's catchment from −1.64 to −0.40; and 2010 at −2.06 m w.e., attributed to the Eyjafjallajökull eruption
13. Annals of Glaciology — Estimating local surface glacier mass balance from migration of the 1918 Katla eruption tephra layer on Sléttjökull. The 1918 tephra layer at 200–300 m depth in the central ice cap and up to 460 m at the western caldera rim, outcropping on Sléttjökull at about 900–1,000 m a.s.l., and its use as a mass-balance marker from 1988 to 2020 — the mechanism by which old ash reaches an exposed ice surface
14. Dragosics et al. — Insulation effects of Icelandic dust and volcanic ash on snow and ice (Arabian Journal of Geosciences, 2016). Laboratory and outdoor experiments with 2010 Eyjafjallajökull ash: maximum melt at a layer thickness of 1–2 mm, with insulation beginning only at 9–15 mm for 500 μm ash and about 13 mm for 90 μm ash — the basis for correcting the claim that ash keeps the cave cool
15. Óladóttir et al. — Katla volcano, Iceland: magma composition, dynamics and eruption frequency as recorded by Holocene tephra layers (Bulletin of Volcanology, 2008). 208 tephra layers across about 8,400 years of Holocene activity, divided into eight intervals of 510–1,750 years and two cycles, with Katla presently in the first interval of the third cycle — a stage of uniform magma composition and relatively low eruption frequency
16. Tómasson — The jökulhlaup from Katla in 1918 (Annals of Glaciology). Peak discharge above 3 × 10⁵ m³/s; about 8 km³ of floodwater with roughly 60% in the first eight hours; about 2.5 km³ and 2.5 billion tonnes of material; roughly 0.5 km³ of ice moved; 0.7 km³ of airborne tephra; the eruption onset on 12 October 1918; and the Kötlutangi headland of some 14 km² added to the coast
17. Smithsonian Global Volcanism Program — Katla. A summit elevation of 1,490 m; the 1918 eruption dated 12 October to 4 November at VEI 4; the 1755–56 eruption from 17 October to 13 February at a possible VEI 5 with large jökulhlaups and evacuations; and Eldgjá at about 18 km³ of lava and 1.3 km³ of tephra
18. Katla UNESCO Global Geopark — Katla geosite. A caldera of about 100 km² in a volcanic system some 110 km long and 30 km wide; at least 20 eruptions since settlement plus three possible small eruptions in 1955, 1999 and 2011 that did not break the ice; jökulhlaup discharges of 100,000–300,000 m³/s; and the estimate that an eruption melts 5–10% of the ice cap, which then takes decades to recover
19. Katla UNESCO Global Geopark — Kötlujökull geosite. Kötlujökull leaving the eastern side of Mýrdalsjökull through a breach in the Katla caldera between Hábunga and Kötlukollar and spreading between Sandfell and Hafursey; its ice caves; and the fact that most jökulhlaups from Katla in the last 1,100 years have passed through this glacier, including 1721 and 1755
20. Katla UNESCO Global Geopark — Mýrdalsjökull geosite. The Geopark's own figures of 535 km² and 140 km³, a mean thickness of 230 m and a maximum near 740 m in the northern caldera, and summits of Goðabunga 1,510 m, Hábunga 1,497 m, Austmannsbunga 1,377 m and Kötlukollar 1,320 m — the alternative set to the inventory's
21. Vatnajökulsþjóðgarður — Ice Cave Tours and Glacier Hikes: decision on withdrawal of advertisement and extension of contracts. Contracts expiring 30 September 2024, extended through 30 October; the ban to 31 October on all ice formations under an ice roof, overhanging, slanted or arched; new contracts taking effect 1 November 2024; and the requirements on guide education (Jökla 3 or equivalent), guests per guide and their registration, and equipment
22. Iceland Review — Stricter Safety Rules Imposed for Vatnajökull Ice-Cave Tours (16 October 2024). The post-collapse contract conditions at Breiðamerkurjökull: a designated lead guide, daily joint safety assessment of caves and overhanging ice, waiver of compensation claims over access restrictions, and a professional oversight council funded by per-client fees, drawn from the park, operators, SAF, FASK and the mountain guides' association
23. The Reykjavík Grapevine — Visitor Numbers May Be Limited On Vatnajökull Ice Cave Tours (16 September 2025). The Vatnajökull cave season running October to April with caves closed May through September; 8–16 guests per guide by tour type; 30 of 34 applicant companies permitted for 2025–26; two-year contracts moving toward five; a trade worth ISK 4–5 billion a year; and the Nature Conservation Agency's power to cap total visitors
24. The Reykjavík Grapevine — Debate Over Five- Or Six-Month Summer Halt On Ice Cave Tours (11 March 2025). The professional advisory board's recommendation of a 15 April to 15 October halt inside Vatnajökull National Park, the operators' split over the dates, and the explicit limitation of the proposal to the national park
25. The Reykjavík Grapevine — Breaking Point: Fatal Ice Cave Accident Raises Big Questions For Tourism Safety (6 September 2024). The 25 August 2024 ice-wall collapse at Breiðamerkurjökull: one American visitor killed and his pregnant fiancée injured from a group of 23; about 200 rescuers and two helicopters searching two days for people who did not exist; the operator Ice Pic Journeys; and the account of a system resting on annual park permits and good faith
26. Iceland Review — Ice Cave Tours Unregulated Beyond Vatnajökull (3 April 2025). Dagbjartur Brynjarsson of the Icelandic Tourist Board stating that no rules exist for ice-cave tours outside Vatnajökull National Park, that the Board has no authority to issue them, and that a ministerial regulation or an act of parliament would be required — the legal position that governs the Katla ice cave
27. Ferðamálastofa / Icelandic Tourist Board — Safety plans. The requirement under Act on the Icelandic Tourist Board No. 96/2018 that every organised tour type have a safety plan comprising risk assessment, operating procedures covering staff qualifications and customer ratios, contingency plan and incident report; in Icelandic and English; reviewed annually and after incidents; audited at random; with daily fines of ISK 50,000–500,000
28. Ferðamálastofa — Leiðbeinandi reglur um öryggismál. That the Board's safety requirements — including the knowledge, experience and training expected of guides on glacier trips — were issued as advisory guidance pending binding regulation, not as enforceable rules
29. Almannavarnir — Viðbragðsáætlun vegna Kötlu og Eyjafjallajökuls. The civil-protection plan: Katla erupting roughly once or twice a century; modelled flood routes including Sólheimasandur and Markarfljót; alerting by SMS to phones in the affected area; and the warning that the time available to evacuate is short
30. Vatnajökulsþjóðgarður — news archive. The establishment of the Nature Conservation Agency of Iceland on 1 January 2025, which now administers Vatnajökull National Park and therefore the ice-cave contracts
31. Arctic Adventures — Katla Ice Cave Tour. The tour operating on Kötlujökull; the marketing claim of 'Iceland's only year-round natural ice cave'; the Icewear Magasin meeting point in Vík; a three-hour duration; a minimum age of 6; provided helmet, crampons and safety gear; and a starting price near US$195
32. Tröll Expeditions — Katla Volcano Ice Cave. Meeting at the Vík Inn; about three hours with a 40-minute super-jeep transfer each way; helmets, headlamps and crampons provided; minimum age 8 in winter and 6 in summer; year-round operation; and a starting price near US$240
33. Katlatrack — Katla Ice Cave. The cave placed in Kötlujökull; ISK 39,900; three to four hours; meeting at Austurvegur 16 in Vík; minimum age 12; operating all year subject to conditions; and the unsupported commercial claim that the ice is 800 years old
34. South Adventure — Katla Ice Cave Tour. ISK 29,990 for a three-hour tour on Kötlujökull, daily year-round, with four departures a day from the Icewear car park in Vík — the lower end of the current price band
35. Perlan — A Complete Guide to the Katla Ice Cave. A widely read guide placing the cave in Kötlujökull and stating it can be visited any month — and containing the incorrect explanation that natural ice caves form 'when the water underneath a glacier freezes', quoted here as the claim being corrected
36. Ferðamálastofa — Ferðaþjónusta í tölum, samantekt fyrir árið 2025. About 2.27 million departing foreign passengers through Keflavík in 2025 and 79% of foreign travellers visiting South Iceland — the pressure the south coast is absorbing
37. UNESCO World Heritage Centre — Vatnajökull National Park, Dynamic Nature of Fire and Ice. Iceland's glacier World Heritage property, inscribed in 2019 under criterion (viii), which contains neither Mýrdalsjökull nor Kötlujökull — the boundary that decides which rules apply

Official and scientific bodies are the authority for safety, regulatory and scientific claims. Commercial operators are used only for practical detail such as tour length, meeting points and indicative pricing — never for a safety or scientific statement.