Iceland Jóhann Heiðar Árnason · CC BY-SA 3.0
The descent
The entrance, at 30 m.
The real relief above Hellnahellir, measured on the Copernicus model every 30 m, and the cave going down at the same vertical scale.
The depth is the one published by those who explored it; the shape of the galleries is a sketch, not a survey. No depth has been published for this cave yet.
30m
Entrance altitude
from the 30 m relief model
4°C
Inside, all year
the yearly average outside, at the entrance
Inside and outside
4 °C inside, all year.
Deep inside, a cave keeps the average temperature of the year outside: about 4 °C here, in January and in August. In July the afternoon reaches 15 °C at the entrance, 10 °C warmer than inside: take a jacket. The wettest months are in December: water rises fast underground, so never go in without a guide after heavy rain.
- 1°-3°Jan
- 2°-3°Feb
- 3°-2°Mar
- 6°1°Apr
- 9°3°May
- 13°7°Jun
- 15°9°Jul
- 14°8°Aug
- 10°6°Sep
- 6°2°Oct
- 3°-1°Nov
- 1°-3°Dec
Outside: afternoon and night averages for 1991–2020 (NASA POWER) brought to the altitude of the entrance. Inside: the yearly average, which deep parts of a cave keep. Near the entrance it follows the weather a little.
Cave in Iceland
Hellnahellir is a cave in Iceland. The entrance is at 30 m. It has an underground river.
Getting there.
- Wild cave: only with caving equipmentNo paths or lights inside. Go only with a caving club or a qualified guide.
- Hvolsvöllurnearest town · 13 km in a straight line
- Viewpointsnearest viewpoint · 1.9 km from the entrance
- Reykjavík Domestic Airport (RKV)nearest airport with scheduled flights · 82 km in a straight lineCar hire at RKV airport (Reykjavík)Discover Cars · sponsored link↗
Plan the visit
Guided tours, a bed nearby, a car.
Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.
The water
The Ytri-Rangá runs highest from November to April.
The Ytri-Rangá carries about 345 m³/s on average here. It runs highest from November to April.
- 815 m³/sJan
- 881 m³/sFeb
- 801 m³/sMar
- 682 m³/sApr
- 511 m³/sMay
- 308 m³/sJun
- 183 m³/sJul
- 170 m³/sAug
- 424 m³/sSep
- 530 m³/sOct
- 609 m³/sNov
- 706 m³/sDec
From about 170 m³/s in the lowest month to 881 m³/s in the highest. Its basin above this point covers 7,185 km².
Estimate: long-term flow from the HydroATLAS model (WaterGAP, 1971–2000) shaped by the monthly rain, snow and temperature of the area (NASA POWER). Dams change it. Not a forecast.
From above.
The ground above the cave, with the relief shaded, the line of the section and what people have mapped around the entrance.
N
1.5 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 6.0 × 6.0 km, north up. The line is the section above. Points © OpenStreetMap contributors.
Around the entrance.
- 1viewpoints within 3 km
- 2named waterfalls within 4 kmÆgissíðufoss, Árbæjarfoss
- 19car parks within 2 km
- 1bus stops within 2 km
- 2campsites within 8 kmÁrhús, Hella Gaddstaðaflatir
- 9hotels and guesthouses within 8 kmHotel Rangá, Hestheimar, Aurora Lodge Hotel and 6 more
- 2restaurants and cafés within 3 km
- other cave entrances within 3 km
- springs within 2 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- marked hiking routes within 3 km
- climbing crags within 3 km
- information boards and visitor centres within 3 km
Counted in OpenStreetMap, the map anyone can edit, around the entrance. A low number may just mean nobody has mapped it yet. © OpenStreetMap contributors (ODbL).
Towns nearby
- Hvolsvöllur13 km in a straight line
In our other atlases
What else is around Hellnahellir.
The river at the entrance, the waterfalls, the lakes, the mountains and volcanoes above, the canyons, beaches and islands nearby — from our other atlases.
Cascadyas2 waterfalls within 5 km
Peakyas2 mountains within 10 kmFigures from the sister sites' databases (Wikidata, HydroATLAS, GeoNames, NOAA, OpenStreetMap). Links open when each site is online.
Month by month
The weather outside, at the entrance.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon | 1 | 2 | 3 | 6 | 9 | 13 | 15 | 14 | 10 | 6 | 3 | 1 |
| Afternoon | 1 | 2 | 3 | 6 | 9 | 13 | 15 | 14 | 10 | 6 | 3 | 1 |
| Night | -3 | -3 | -2 | 1 | 3 | 7 | 9 | 8 | 6 | 2 | -1 | -3 |
| Rain (mm) | 179 | 163 | 160 | 121 | 92 | 85 | 104 | 115 | 178 | 144 | 145 | 182 |
| Rainy days | 21 | 20 | 20 | 17 | 16 | 16 | 18 | 19 | 20 | 18 | 19 | 20 |
| Sun hours/day | 0.3 | 1.0 | 4.0 | 6.9 | 8.1 | 8.0 | 6.8 | 5.8 | 3.6 | 2.2 | 0.5 | 0.4 |
| Snow on the ground (cm) | 22 | 22 | 23 | 16 | 6 | 0 | 0 | 0 | 1 | 7 | 13 | 17 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 1 | 1 | -3 | 179 | 0.3 |
| Feb | 2 | 2 | -3 | 163 | 1.0 |
| Mar | 3 | 3 | -2 | 160 | 4.0 |
| Apr | 6 | 6 | 1 | 121 | 6.9 |
| May | 9 | 9 | 3 | 92 | 8.1 |
| Jun | 13 | 13 | 7 | 85 | 8.0 |
| Jul | 15 | 15 | 9 | 104 | 6.8 |
| Aug | 14 | 14 | 8 | 115 | 5.8 |
| Sep | 10 | 10 | 6 | 178 | 3.6 |
| Oct | 6 | 6 | 2 | 144 | 2.2 |
| Nov | 3 | 3 | -1 | 145 | 0.5 |
| Dec | 1 | 1 | -3 | 182 | 0.4 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (30 m) with the standard lapse rate. Not a forecast.
Recent years
Wet years, dry years.
Rain of each month as a share of the 1991–2020 average. A dry year means a lower river and hotter rock; a wet one, more water in the gorge.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020 | 136% | 87% | 100% | 116% | 116% | 141% | 81% | 146% | 122% | 46% | 102% | 76% |
| 2021 | 54% | 60% | 99% | 95% | 75% | 130% | 105% | 90% | 129% | 96% | 131% | 73% |
| 2022 | 141% | 88% | 190% | 71% | 106% | 123% | 133% | 133% | 70% | 67% | 54% | 32% |
| 2023 | 92% | 151% | 31% | 97% | 218% | 151% | 20% | 79% | 101% | 96% | 61% | 77% |
| 2024 | 90% | 68% | 60% | 73% | 135% | 117% | 122% | 115% | 65% | 87% | 117% | 123% |
| 2025 | 94% | 124% | 117% | 71% | 113% | 112% | 125% | 104% | 84% | 103% | 34% | 71% |
130% or more: wet month 70% or less: dry month
Caves nearby.
Hellnahellir
Iceland
- —Depth
- —Galleries
- 30 mEntrance altitude
- 4 °CInside, all year
Raufarhólshellir
Iceland · 50 km
- —Depth
- —Galleries
- 167 mEntrance altitude
- 4 °CInside, all year
Landmannahellir
Iceland · 62 km
- —Depth
- —Galleries
- 593 mEntrance altitude
- 0 °CInside, all year
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q13635767) · CC0 |
|---|---|
| The relief above, the entrance altitude, the section and the 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| River flow and basin | HydroATLAS / RiverATLAS v1.0 (Linke et al. 2019) · CC BY 4.0 |
| Climate | NASA POWER, 1991–2020 |
| Entrances, springs, sinkholes, opening hours and what is around | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Rivers, waterfalls, lakes, mountains, canyons, beaches and islands nearby | Coastya, Lakeyas, Peakyas, Cascadyas, Islandyas, Riveryas |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers, canyons, caves, dark skies, viewpoints, birdwatching or forests?
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