France Water gap
Portes Sarrazines
199 m of rock, cut by the Le Grand Journans.
Björn S. · CC BY-SA 3.0
The cut
199 metres, to scale.
A slice through Portes Sarrazines where it is deepest and narrowest, measured on the Copernicus relief model every 30 m. Same scale as the landmark standing on the floor.
Standing on the floor, to scale: Great Pyramid · 139 m
Depth is measured to the lower rim; the width is from rim to rim. A 30 m relief model smooths the narrowest walls, so a slot canyon reads shallower than it is.
199m
Depth
measured on the 30 m relief model
13.5km
Rim to rim
measured on the 30 m relief model
28°
Steepest wall
average over 300 m, from the relief
554m
Floor altitude
Rim to floor
7 °C warmer at the bottom.
In July the afternoon reaches 25 °C on the floor, against 17 °C on the rim. The best months to hike are in June and in September. The rim freezes at night from November to April.
- 4°-4°Jan
- 5°-3°Feb
- 9°2°Mar
- 14°7°Apr
- 18°10°May
- 22°15°Jun
- 25°17°Jul
- 24°17°Aug
- 20°13°Sep
- 15°8°Oct
- 9°1°Nov
- 4°-3°Dec
Afternoon highs, 1991–2020 averages (NASA POWER) brought to the altitude of the rim and of the floor with the standard lapse rate (6.5 °C per 1 000 m). Shade, wind and rock change this on the day. Not a forecast.
Portes Sarrazines is a water gap in France, cut by the Le Grand Journans river. The relief model measures 199 m from the floor to the lower rim, and 1,132 m to the higher one. Rim to rim it is 14 km wide where the cut was taken.
Getting there.
- Gexnearest town · 1.9 km in a straight line
- Parking 610 m awaynearest car park in OpenStreetMap, straight line
- Viewpointsnearest viewpoint · 2.8 km from the floor
- Geneva International Airport (GVA)nearest airport with scheduled flights · 13 km in a straight lineCar hire at GVA airport (Geneva)Discover Cars · sponsored link↗
- In June and in Septemberbest months to hike (estimate)
Plan the visit
Guided hikes, 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 the sky.
The canyon from above, with the relief shaded, the line of the cut, the river and what people have mapped around it.
N
6 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 24 × 24 km, north up. The line is the cut above. Points © OpenStreetMap contributors.
Around the canyon.
- 26viewpoints within 5 kmSources de l'Allondon, Belvédère du Turet, Vesancy - Bassin Lémanique and 23 more
- 67marked hiking routes within 4 km
- 1climbing crags within 3 kmSalle de Perdtemps
- 4footbridges and suspension bridges within 3 km
- 72car parks within 3 km
- 22information boards and visitor centres within 4 km
- 3bus stops within 2 km
- 8campsites within 8 kmHuttopia Camping Divonne les Bains, Les Genêts, Caravaning En Vendôme and 5 more
- 49hotels and guesthouses within 8 kmHôtel d'Ornex, Gabelou Hôtel, La Couronne and 46 more
- 14restaurants and cafés within 4 km
- via ferrata routes within 4 km
- rafting, canoe, kayak or canyoning spots within 4 km
- swimming spots within 3 km
- named waterfalls within 4 km
- caves within 3 km
Counted in OpenStreetMap, the map anyone can edit, around the floor of the canyon. A low number may just mean nobody has mapped it yet. © OpenStreetMap contributors (ODbL).
Towns nearby
- Gex1.9 km in a straight line
- Cessy3.9 km in a straight line
- Échenevex4.0 km in a straight line
- Ségny6.0 km in a straight line
- Sauverny6.9 km in a straight line
- Chevry7.1 km in a straight line
- Divonne-les-Bains7.5 km in a straight line
- Ornex9.3 km in a straight line
In our other atlases
What else is around Portes Sarrazines.
The river that carved it, the waterfalls inside it, the mountains on the rim, the lakes, beaches and island nearby — from our six sister atlases, each with its own figures.
Peakyas16 mountains within 15 km
Lakeyas1 lakes within 15 kmComing soonFigures from the sister sites' databases (Wikidata, HydroATLAS, GeoNames, NOAA, OpenStreetMap). Links open when each site is online.
Month by month
The weather, at the floor and at the rim.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon · floor | 4 | 5 | 9 | 14 | 18 | 22 | 25 | 24 | 20 | 15 | 9 | 4 |
| Afternoon · rim | -4 | -3 | 2 | 7 | 10 | 15 | 17 | 17 | 13 | 8 | 1 | -3 |
| Night · rim | -10 | -10 | -6 | -2 | 2 | 6 | 8 | 7 | 3 | 0 | -5 | -9 |
| Rain (mm) | 96 | 75 | 92 | 82 | 117 | 107 | 101 | 107 | 80 | 103 | 100 | 108 |
| Rainy days | 13 | 11 | 12 | 13 | 16 | 15 | 14 | 13 | 12 | 13 | 14 | 14 |
| Sun hours/day | 3.3 | 4.4 | 5.5 | 6.3 | 6.6 | 8.5 | 8.9 | 7.9 | 6.9 | 5.0 | 3.1 | 2.6 |
| Snow on the ground (cm) | 16 | 15 | 9 | 4 | 1 | 0 | 0 | 0 | 0 | 2 | 8 | 15 |
| Afternoon · floor | Afternoon · rim | Night · rim | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 4 | -4 | -10 | 96 | 3.3 |
| Feb | 5 | -3 | -10 | 75 | 4.4 |
| Mar | 9 | 2 | -6 | 92 | 5.5 |
| Apr | 14 | 7 | -2 | 82 | 6.3 |
| May | 18 | 10 | 2 | 117 | 6.6 |
| Jun | 22 | 15 | 6 | 107 | 8.5 |
| Jul | 25 | 17 | 8 | 101 | 8.9 |
| Aug | 24 | 17 | 7 | 107 | 7.9 |
| Sep | 20 | 13 | 3 | 80 | 6.9 |
| Oct | 15 | 8 | 0 | 103 | 5.0 |
| Nov | 9 | 1 | -5 | 100 | 3.1 |
| Dec | 4 | -3 | -9 | 108 | 2.6 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the floor (554 m) and the rim (1,686 m) with the standard lapse rate. Not a forecast.
Photographs
Seen from the trail.
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 | 56% | 175% | 92% | 50% | 93% | 142% | 37% | 99% | 104% | 203% | 25% | 89% |
| 2021 | 116% | 62% | 57% | 47% | 132% | 121% | 171% | 61% | 82% | 77% | 57% | 157% |
| 2022 | 50% | 116% | 24% | 120% | 43% | 99% | 32% | 67% | 221% | 88% | 127% | 124% |
| 2023 | 91% | 12% | 145% | 127% | 61% | 59% | 80% | 82% | 77% | 164% | 260% | 162% |
| 2024 | 122% | 102% | 103% | 115% | 146% | 117% | 90% | 92% | 256% | 146% | 69% | 110% |
| 2025 | 155% | 52% | 50% | 104% | 81% | 101% | 109% | 100% | 201% | 151% | 147% | 29% |
130% or more: wet month 70% or less: dry month
Compare with the neighbours.
Portes Sarrazines
France
- 199 mDepth
- 14 kmRim to rim
- —Length
- 28°Steepest wall
Gorges du Val du Fier
France · 47 km
- 761 mDepth
- 10 kmRim to rim
- 3.5 kmLength
- 30°Steepest wall
Where these figures come from
| Name, type, published depth and length | Wikidata (Q3399242) · CC0 |
|---|---|
| The cut: depth, width, wall and 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Climate | NASA POWER, 1991–2020 |
| Viewpoints, trails, bridges and the river line | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Rivers, waterfalls, mountains, lakes, 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
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