Japan fum3670045 · CC BY 3.0
The cut
429 metres, to scale.
A slice through Sanbaseki Gorge 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: Big Ben · 96 m · Eiffel Tower · 330 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.
429m
Depth
measured on the 30 m relief model
5.7km
Rim to rim
measured on the 30 m relief model
24°
Steepest wall
average over 300 m, from the relief
141m
Floor altitude
Rim to floor
3 °C warmer at the bottom.
In August the afternoon reaches 32 °C on the floor, against 29 °C on the rim. The best months to hike are in April and in October. The rim freezes at night from December to February. The wettest months are from July to October.
- 6°3°Jan
- 8°5°Feb
- 12°9°Mar
- 19°16°Apr
- 24°21°May
- 27°24°Jun
- 31°28°Jul
- 32°29°Aug
- 28°25°Sep
- 22°19°Oct
- 16°13°Nov
- 9°6°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.
Ravine on Fujioka, Japan
Sanbaseki Gorge is a canyon in Japan, cut by the Kanna River. The relief model measures 429 m from the floor to the lower rim. Rim to rim it is 5.7 km wide where the cut was taken.
Getting there.
- Nagatoronearest town · 7.7 km in a straight line
- Parking 450 m awaynearest car park in OpenStreetMap, straight line
- Tokyo Haneda International Airport (HND)nearest airport with scheduled flights · 94 km in a straight lineCar hire at HND airport (Tokyo)Discover Cars · sponsored link↗
- In April and in Octoberbest 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.
The river
The Kanna River runs highest from July to October.
The Kanna River carries about 2.6 m³/s on average here. It runs highest from July to October.
- 0.5 m³/sJan
- 1.0 m³/sFeb
- 2.8 m³/sMar
- 4.2 m³/sApr
- 4.4 m³/sMay
- 4.7 m³/sJun
- 6.2 m³/sJul
- 5.5 m³/sAug
- 6.8 m³/sSep
- 7.7 m³/sOct
- 4.0 m³/sNov
- 1.0 m³/sDec
From about 0.52 m³/s in the lowest month to 7.7 m³/s in the highest. Its basin above this point covers 342 km².
The Kanna 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 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
3 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 12 × 12 km, north up. The line is the cut above. Points © OpenStreetMap contributors.
Around the canyon.
- 2marked hiking routes within 4 kmKFT - G1 - Sanbasekikyo no michi, KFT - G34 - Sakurayama no michi
- 3footbridges and suspension bridges within 3 km
- 8car parks within 3 km
- 2information boards and visitor centres within 4 km
- 7bus stops within 2 km
- 4campsites within 8 km長瀞オートキャンプ場, ウォーターパーク長瀞, 城峯公園キャンプ場 and 1 more
- 2hotels and guesthouses within 8 km民宿 やなぎや, いこいの村ヘリテイジ美の山
- 2restaurants and cafés within 4 km
- viewpoints within 5 km
- via ferrata routes within 4 km
- climbing crags within 3 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
- Nagatoro7.7 km in a straight line
- Minano8.8 km in a straight line
- Manba10 km in a straight line
- Kodamachō-kodamaminami11 km in a straight line
- Uetake11 km in a straight line
- Ogano12 km in a straight line
- Fujioka14 km in a straight line
- Yoshii14 km in a straight line
In our other atlases
What else is around Sanbaseki Gorge.
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.
Riveryas1 rivers in the canyon
Peakyas12 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 | 6 | 8 | 12 | 19 | 24 | 27 | 31 | 32 | 28 | 22 | 16 | 9 |
| Afternoon · rim | 3 | 5 | 9 | 16 | 21 | 24 | 28 | 29 | 25 | 19 | 13 | 6 |
| Night · rim | -6 | -5 | -2 | 3 | 10 | 15 | 19 | 20 | 16 | 9 | 2 | -3 |
| Rain (mm) | 57 | 53 | 87 | 96 | 114 | 147 | 194 | 154 | 183 | 168 | 70 | 59 |
| Rainy days | 8 | 8 | 11 | 10 | 12 | 17 | 20 | 18 | 15 | 12 | 9 | 9 |
| Sun hours/day | 4.5 | 5.2 | 5.6 | 6.3 | 6.5 | 5.0 | 4.5 | 5.7 | 4.6 | 4.6 | 4.8 | 4.3 |
| Snow on the ground (cm) | 17 | 16 | 13 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 5 | 14 |
| Afternoon · floor | Afternoon · rim | Night · rim | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 6 | 3 | -6 | 57 | 4.5 |
| Feb | 8 | 5 | -5 | 53 | 5.2 |
| Mar | 12 | 9 | -2 | 87 | 5.6 |
| Apr | 19 | 16 | 3 | 96 | 6.3 |
| May | 24 | 21 | 10 | 114 | 6.5 |
| Jun | 27 | 24 | 15 | 147 | 5.0 |
| Jul | 31 | 28 | 19 | 194 | 4.5 |
| Aug | 32 | 29 | 20 | 154 | 5.7 |
| Sep | 28 | 25 | 16 | 183 | 4.6 |
| Oct | 22 | 19 | 9 | 168 | 4.6 |
| Nov | 16 | 13 | 2 | 70 | 4.8 |
| Dec | 9 | 6 | -3 | 59 | 4.3 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the floor (141 m) and the rim (594 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 | 143% | 60% | 118% | 147% | 80% | 143% | 212% | 36% | 96% | 127% | 26% | 33% |
| 2021 | 108% | 98% | 133% | 88% | 105% | 99% | 142% | 191% | 88% | 54% | 83% | 137% |
| 2022 | 31% | 86% | 81% | 171% | 106% | 80% | 147% | 119% | 138% | 52% | 111% | 65% |
| 2023 | 28% | 71% | 120% | 96% | 163% | 257% | 49% | 100% | 92% | 61% | 84% | 45% |
| 2024 | 75% | 178% | 174% | 111% | 169% | 169% | 71% | 233% | 79% | 121% | 160% | 22% |
| 2025 | 42% | 32% | 135% | 109% | 183% | 100% | 91% | 66% | 122% | 95% | 34% | 79% |
130% or more: wet month 70% or less: dry month
Compare with the neighbours.
Sanbaseki Gorge
Japan
- 429 mDepth
- 5.7 kmRim to rim
- —Length
- 24°Steepest wall
Where these figures come from
| Name, type, published depth and length | Wikidata (Q11356265) · CC0 |
|---|---|
| The cut: depth, width, wall and 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 |
| 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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