A caver stands at the foot of a large ice cave, on orange ground.

Fire Under Ice

Exploring Iceland's glaciovolcanic caves

2025–2027

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The project

The ice changes, the heat stays.

Where a volcano melts a glacier from below, caves open in the ice. They can vanish within a year. We go back, survey them and measure what changes.

Ordinary glacier caves are cut by surface meltwater. These are melted from below by geothermal heat and steam. The ceiling is ice. The air may not be breathable.

Cut-away drawing of a glacier on a volcano, with heat and steam rising from below and caves opening in the ice.
Glaciovolcanic cave system. Original artwork by Lee Florea.

2026 fieldwork carried out under a research permit.

2025–2027

Three years, one island

  1. Plan of the Hveradalur cave system, survey 2025, north up.

    2025 Reconnaissance

    Kverkfjöll, Dyngjujökull

    Four people on the trail of Gérald Favre's Swiss team, which explored Kverkfjöll from the 1980s to 2008: the deepest glacier cave known, about 500 m deep and 2.8 km long in 1984. The great cave stayed closed. Near the hut, on top of the volcano, we found the Hveradalur system: almost 1 km.

  2. Sala Rosa dei Beati in Freyja Hellir, a domed hall of ice with concentric blue rings.

    2026 Discovery

    Kverkfjöll, Torfa caldera

    A thaw lake flooded most of Hveradalur: of almost 1 km, 150 m remained above water. On Kaldaklofsjökull we found Freyja Hellir, a new glaciovolcanic cave: almost 1500 m surveyed, with a hall about 50 m across.

  3. Map of south Iceland showing Torfajökull, the primary 2027 target, and the reconnaissance options Mýrdalsjökull and Grímsvötn.

    2027 Expansion

    Torfajökull, plus one reconnaissance

    Back to the Torfa caldera, this time on its main glacier. Reconnaissance on Mýrdalsjökull (Katla), or the Grímsvötn cauldrons from the south. Lidar joins the survey. About 10–31 July 2027, with the 2026 team.

The 2006 survey of the Hveradalur cave, drawn in blue over a 2024 satellite image. 2006
The 2025 survey of the Hveradalur cave, drawn in red over the same 2024 satellite image. 2025
Same heat, different ice. Between 2006 and 2025 a lake melted the ice that held this cave at least once. The 2025 cave sits in different ice, yet its main corridor still follows the 2006 route. 2006 survey: G. Favre et al., Hypogées 69. Background: satellite image, 2024 (Google Earth, Image © 2026 Airbus).
Map of Iceland marking Kverkfjöll and Dyngjujökull (2025), the Torfa caldera (2026 and 2027) and the 2027 reconnaissance options.
2025: Kverkfjöll, Dyngjujökull. 2026: Kverkfjöll, Torfa caldera. 2027: Torfajökull, plus one reconnaissance target.

Places

Where we work

Two cavers on a dark mound under a scalloped ice ceiling, orange mineral crust below.

2026–2027

Torfa caldera

Freyja Hellir, a new glaciovolcanic cave on Kaldaklofsjökull: almost 1500 m surveyed, with a hall about 50 m across.

  • Two people with yellow rucksacks wade across a wide, shallow river below green hills.
  • A thermometer probe held into a dark rippled pool rimmed with orange and rust-coloured mineral deposits.
  • A hand holds a thermal camera whose screen shows a warm stream in rainbow colours, inside an ice cave.

See all 9 photos

Steam rises from a deep ice cauldron with a green lake at its bottom; a caver in yellow watches from the rim.

2025–2026

Kverkfjöll

On the trail of Gérald Favre's Swiss team: the Hveradalur system, almost 1 km, then flooded by a thaw lake.

  • A caver stands in a dark ice cave whose scalloped ceiling glows white, the floor lit orange.
  • A turquoise lake below a glacier front, with red volcanic slopes on the left and dark rocks in front.
  • A caver in a full-face respirator stands on orange ground beside an ice wall, steam behind.

See all 10 photos

Watch

Kverkfjöll over time

Photogrammetry, cave surveys and timelapse.

Video still: Kverkfjöll over time. Play video on YouTube

Science and monitoring

From 0.2 °C to 59.4 °C in one cave.

Dark, oligotrophic, volcanic environments: Earth analogues for icy moons such as Enceladus.

3D model of Efri Hveradalur, Kverkfjöll, from drone photogrammetry, with Lake Galtarlón in front.
Efri Hveradalur, Kverkfjöll, 2026: 3D model from drone photogrammetry, Lake Galtarlón in front.

In the field

What the ice demands

The team

Thirteen cavers in 2026

Consorzio Speleologi Ipogenici

From different caving groups across Italy, Indipendenti in spirit, Ipogenici by vocation.

The name nods to the Italian band CSI, Consorzio Suonatori Indipendenti: a team from different regions and caving groups needed an informal name, and Consorzio Speleologi Indipendenti fitted. Ipogenici replaced Indipendenti because hypogenic caves are what we look for.

Core team

  • Andrea Benassi Andrea Benassi Research, site selection, team building, public relations PhD in Anthropology. Advisor to the Italian Speleological Society (SSI). Has organised over 30 international expeditions.
  • Lorenzo Bordin Lorenzo Bordin Logistics, partner and park relations, data processing, publications PhD in Theoretical Physics. SSI instructor. Ice caves, cave survey and drone photogrammetry.
  • Maria F. Trombini Maria F. Trombini Food supplies and rations, drone photogrammetry SSI speleology instructor. Ice caves since 2023; expeditions in Italy, France, Slovenia, Albania, Austria, UK.
  • Cristian Monticone (Lazzaro) Cristian Monticone (Lazzaro) Lead explorer in the most hazardous passages Vice President, Gruppo Speleologico Piemontese; CNSAS. Breathing apparatus and confined spaces.
  • Mattia Gerbaudo (Jerba) Mattia Gerbaudo (Jerba) Technical gear, confined-space safety, high-risk descents Industrial safety specialist. CNSAS rescuer, CAI mountaineering instructor. Gas and safety lead.

Exploration and field operations

  • Carlo Urbanet Carlo Urbanet Exploration, field coordination, food and medical supplies Engineer, National Speleology Instructor (SSI), CNSAS technician. Explorations in Ethiopia, Iran, Brazil.
  • Ivan Vicenzi Ivan Vicenzi Exploration, field support, photography Rescue operator for over 23 years and technical diver. Expeditions to West Papua, Laos, Honduras.
  • Marco Ettrapini Marco Ettrapini Exploration, field support Chemist and assistant speleology instructor. Mountaineering, rock and ice climbing, canyoning.

Science and confined spaces

  • Paolo Turrini Paolo Turrini Microbiological research and sampling (Bicocca) PhD in Microbiology. Rope access and confined-space specialist; caving in Indonesia, Mexico, Morocco.
  • Lorenzo Scialò Lorenzo Scialò Exploration, confined spaces, biological sampling support Rope access technician and industrial rescuer. Expeditions to Mexico, Greece, Albania, Montenegro.
  • Katia Zampatti Katia Zampatti Exploration, confined spaces, biological sampling support Industrial rescuer, canyoner, alpinist. Member of the Italian Speleological Society. Caving in Norway and Iceland.

Documentation

  • Tommaso Biondi Tommaso Biondi Photography, filming, documentary Caving and mountain documentary maker, award-winning. Films in Africa, South America and West Papua.
  • Paolo Testa Paolo Testa Photography National Speleology Instructor (CAI), caving since 1987. Founded Progetto Speleologia Glaciale in 2008.

Press and talks

Who hears about it

Articles

Talks

TV

Partners

Who backs us

The silhouette of a caver against glowing blue ice.

Contact

Write to us

2027 expedition: about 10–31 July. For partnerships, press or talks, write to the address below.