Gabon Olivier Testa · CC BY-SA 4.0
The descent
The entrance, at 91 m.
The real relief above Iroungou cave, 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.
91m
Entrance altitude
from the 30 m relief model
26°C
Inside, all year
the yearly average outside, at the entrance
Inside and outside
26 °C inside, all year.
Deep inside, a cave keeps the average temperature of the year outside: about 26 °C here, in January and in August. The best months to escape the heat are all year round. The wettest months are from March to April and from October to November: water rises fast underground, so never go in without a guide after heavy rain.
- 30°23°Jan
- 30°23°Feb
- 30°24°Mar
- 30°24°Apr
- 30°23°May
- 30°22°Jun
- 30°20°Jul
- 31°21°Aug
- 32°22°Sep
- 30°22°Oct
- 29°23°Nov
- 29°23°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.
Archaeological site in cave in Gabon
Iroungou cave is a cave in Gabon. The entrance is at 91 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.
- Mouilanearest town · 0.2 km in a straight line
- M'Vengue El Hadj Omar Bongo Ondimba International Airport (MVB)nearest airport with scheduled flights · 266 km in a straight lineCar hire at POG airport (Port Gentil)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 Ngounié runs highest from November to January.
The Ngounié carries about 464 m³/s on average here. It runs highest from November to January. It is lowest from July to September.
- 590 m³/sJan
- 411 m³/sFeb
- 456 m³/sMar
- 517 m³/sApr
- 487 m³/sMay
- 310 m³/sJun
- 163 m³/sJul
- 88 m³/sAug
- 118 m³/sSep
- 398 m³/sOct
- 710 m³/sNov
- 748 m³/sDec
From about 88 m³/s in the lowest month to 748 m³/s in the highest. Its basin above this point covers 15,384 km².
The Ngounie River from source to mouth on Riveryas — coming soon
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.
- 4car parks within 2 km
- 2campsites within 8 kmLac bleu, Glamping Mouila
- 3hotels and guesthouses within 8 kmLe Lac Bleu, Mont des Oliviers, Mukab
- other cave entrances within 3 km
- springs within 2 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- viewpoints within 3 km
- marked hiking routes within 3 km
- climbing crags within 3 km
- named waterfalls within 4 km
- information boards and visitor centres within 3 km
- bus stops within 2 km
- restaurants and cafés 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
- Mouila0.2 km in a straight line
- Makanda13 km in a straight line
In our other atlases
What else is around Iroungou cave.
The river at the entrance, the waterfalls, the lakes, the mountains and volcanoes above, the canyons, beaches and islands nearby — from our other atlases.
Riveryas2 rivers at the entranceFigures 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 | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 31 | 32 | 30 | 29 | 29 |
| Afternoon | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 31 | 32 | 30 | 29 | 29 |
| Night | 23 | 23 | 24 | 24 | 23 | 22 | 20 | 21 | 22 | 22 | 23 | 23 |
| Rain (mm) | 174 | 166 | 251 | 245 | 165 | 22 | 4 | 10 | 74 | 333 | 403 | 222 |
| Rainy days | 26 | 25 | 28 | 27 | 24 | 6 | 2 | 4 | 14 | 28 | 29 | 27 |
| Sun hours/day | 4.9 | 4.6 | 5.2 | 5.1 | 4.0 | 2.7 | 2.3 | 1.8 | 2.2 | 3.4 | 3.6 | 3.9 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 30 | 30 | 23 | 174 | 4.9 |
| Feb | 30 | 30 | 23 | 166 | 4.6 |
| Mar | 30 | 30 | 24 | 251 | 5.2 |
| Apr | 30 | 30 | 24 | 245 | 5.1 |
| May | 30 | 30 | 23 | 165 | 4.0 |
| Jun | 30 | 30 | 22 | 22 | 2.7 |
| Jul | 30 | 30 | 20 | 4 | 2.3 |
| Aug | 31 | 31 | 21 | 10 | 1.8 |
| Sep | 32 | 32 | 22 | 74 | 2.2 |
| Oct | 30 | 30 | 22 | 333 | 3.4 |
| Nov | 29 | 29 | 23 | 403 | 3.6 |
| Dec | 29 | 29 | 23 | 222 | 3.9 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (91 m) with the standard lapse rate. Not a forecast.
Photographs
Inside and around.
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 | 31% | 32% | 104% | 22% | 52% | 128% | — | 29% | 29% | 42% | 107% | 41% |
| 2021 | 139% | 31% | 99% | 38% | 57% | 40% | — | 174% | 45% | 28% | 52% | 149% |
| 2022 | 23% | 24% | 106% | 35% | 34% | 22% | — | 17% | 48% | 45% | 60% | 28% |
| 2023 | 50% | 113% | 32% | 65% | 37% | 18% | — | 45% | 38% | 51% | 63% | 60% |
| 2024 | 48% | 53% | 96% | 102% | 58% | 104% | — | 39% | 69% | 23% | 48% | 36% |
| 2025 | 33% | 33% | 46% | 55% | 96% | 312% | — | 12% | 37% | 30% | 28% | 35% |
130% or more: wet month 70% or less: dry month
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q107658890) · 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?
Same idea, other landscapes: field atlases built on open data, month by month, in seven languages.
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Every lake on Earth: water temperature, ice, depth and the shore.Visit 
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