France Chevalier Georges · CC BY-SA 4.0
The descent
The entrance, at 82 m.
The real relief above Rocher de l'Impératrice, 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.
82m
Entrance altitude
from the 30 m relief model
12°C
Inside, all year
the yearly average outside, at the entrance
47m
Rock above
the highest point within 1.5 km
Inside and outside
12 °C inside, all year.
Deep inside, a cave keeps the average temperature of the year outside: about 12 °C here, in January and in August. In August the afternoon reaches 20 °C at the entrance, 8 °C warmer than inside: take a jacket.
- 9°6°Jan
- 9°5°Feb
- 11°6°Mar
- 13°7°Apr
- 15°9°May
- 18°12°Jun
- 20°14°Jul
- 20°14°Aug
- 19°12°Sep
- 16°11°Oct
- 12°8°Nov
- 10°6°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.
Rocher de l'Impératrice is a cave in France. The entrance is at 82 m.
Getting there.
- No public accessProtected for science or for its art. Look for a replica or a visitor centre nearby.
- Plougastel-Daoulasnearest town · 1.8 km in a straight line
- Viewpointsnearest viewpoint · 0.1 km from the entrance
- Brest Bretagne airport (BES)nearest airport with scheduled flights · 7 km in a straight lineCar hire at BES airport (Brest)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.
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.
- 1other cave entrances within 3 kmAbri du rocher de l'Impératrice
- 2springs within 2 kmLa Fontaine Blanche, Fontaine
- 5viewpoints within 3 kmPoint de vue sur la Rade de Brest and 4 more
- 6marked hiking routes within 3 kmPresqu’île de plougastel, Chemin des Douaniers, Brest - Le Faou, Les rives de l'Elorn - Saint-Jean and 3 more
- 6climbing crags within 3 kmRocher de l'Impératrice, Le Cube, Rocher Noël and 3 more
- 165car parks within 2 km
- 11information boards and visitor centres within 3 km
- 70bus stops within 2 km
- 5campsites within 8 kmPlougastel-Daoulas Aire Municipale, Aire de Services de Plougastel, Camping Saint-Jean and 2 more
- 39hotels and guesthouses within 8 kmCouett Hotel, Hôtel L'Évasion, L'Amiraute Hotel and 36 more
- 13restaurants and cafés within 3 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- named waterfalls within 4 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
- Plougastel-Daoulas1.8 km in a straight line
- Le Relecq-Kerhuon2.6 km in a straight line
- Loperhet5.3 km in a straight line
- Guipavas5.4 km in a straight line
- La Forest-Landerneau6.2 km in a straight line
- Dirinon7.8 km in a straight line
- Brest8.2 km in a straight line
- Daoulas9.1 km in a straight line
Month by month
The weather outside, at the entrance.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon | 9 | 9 | 11 | 13 | 15 | 18 | 20 | 20 | 19 | 16 | 12 | 10 |
| Afternoon | 9 | 9 | 11 | 13 | 15 | 18 | 20 | 20 | 19 | 16 | 12 | 10 |
| Night | 6 | 5 | 6 | 7 | 9 | 12 | 14 | 14 | 12 | 11 | 8 | 6 |
| Rain (mm) | 104 | 87 | 66 | 55 | 56 | 54 | 55 | 59 | 45 | 95 | 111 | 110 |
| Rainy days | 18 | 14 | 13 | 12 | 11 | 10 | 11 | 11 | 11 | 15 | 17 | 18 |
| Sun hours/day | 1.6 | 3.0 | 4.6 | 7.3 | 8.2 | 8.5 | 8.3 | 7.3 | 6.6 | 4.1 | 2.2 | 1.4 |
| Snow on the ground (cm) | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 9 | 9 | 6 | 104 | 1.6 |
| Feb | 9 | 9 | 5 | 87 | 3.0 |
| Mar | 11 | 11 | 6 | 66 | 4.6 |
| Apr | 13 | 13 | 7 | 55 | 7.3 |
| May | 15 | 15 | 9 | 56 | 8.2 |
| Jun | 18 | 18 | 12 | 54 | 8.5 |
| Jul | 20 | 20 | 14 | 55 | 8.3 |
| Aug | 20 | 20 | 14 | 59 | 7.3 |
| Sep | 19 | 19 | 12 | 45 | 6.6 |
| Oct | 16 | 16 | 11 | 95 | 4.1 |
| Nov | 12 | 12 | 8 | 111 | 2.2 |
| Dec | 10 | 10 | 6 | 110 | 1.4 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (82 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 | 119% | 147% | 105% | 98% | 53% | 229% | 60% | 113% | 122% | 158% | 71% | 173% |
| 2021 | 104% | 98% | 47% | 24% | 151% | 113% | 143% | 70% | 109% | 132% | 43% | 88% |
| 2022 | 61% | 67% | 69% | 63% | 41% | 134% | 13% | 43% | 181% | 79% | 138% | 143% |
| 2023 | 98% | 16% | 163% | 105% | 75% | 63% | 142% | 95% | 115% | 125% | 135% | 91% |
| 2024 | 107% | 119% | 140% | 98% | 118% | 70% | 151% | 111% | 164% | 108% | 81% | 57% |
| 2025 | 146% | 49% | 37% | 87% | 51% | 56% | 56% | 33% | 133% | 68% | 61% | 78% |
130% or more: wet month 70% or less: dry month
Caves nearby.
Rocher de l'Impératrice
France
- —Depth
- —Galleries
- 82 mEntrance altitude
- 12 °CInside, all year
Kents Cavern
United Kingdom · 240 km
- —Depth
- —Galleries
- 56 mEntrance altitude
- 11 °CInside, all year
Wookey Hole Caves
United Kingdom · 339 km
- —Depth
- 3.7 kmGalleries
- 62 mEntrance altitude
- 10 °CInside, all year
Gough's Cave
United Kingdom · 342 km
- —Depth
- —Galleries
- 67 mEntrance altitude
- 10 °CInside, all year
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q53286344) · 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 |
| 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 |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
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