Paradise Chronicle · CC BY-SA 4.0 · Wikimedia Commons
Mountain in Switzerland
Aletschhorn is a mountain in the Aletschhorn-Bietschhorn Group (Switzerland). Its summit stands 4,194 m above sea level. Its prominence — how far it rises above the highest saddle linking it to a taller summit — is 1,043 m, and the nearest higher ground is 14 km away.
From the lowest point within 5 km (2,294 m), it rises 1,900 m. The steepest side is the east face: 41° on average over the first kilometre. In places the ground near the top reaches 58° — terrain for climbers, not walkers.
The nearest town is Fiesch, 13 km away at 1,052 m: 3,142 m below the summit.
Scores
Two scores out of 10, built only from open data — every part is shown. They describe what the mountain offers, not how safe it is.
Hiking & mountaineering
8.2/10
Difficulty to the top
Alpine climb
Glaciers around the top.
Indicative only — never a safety assessment. Conditions change: ask local guides and check the forecast.
Ski score
9.0/10
Runs by difficulty
Snow season on the slopes (estimate)
Around 2,544 m, in the middle of the ski area: snow from October to June.
76 lifts · lift stations from 2,219 to 2,869 m · 0 km cross-country
Ski (where OpenStreetMap has skiing within 12 km): up to 4 points for the length of downhill runs (300 km or more = 4), 1.5 for the number of lifts (40+), 1.5 for the vertical between lift stations (1,500 m) and 3 for the snow season — a month counts when the estimated mean temperature at the height of the ski area is −1 °C or lower and snow falls or lies there (NASA POWER, 2001–2020). Hiking & mountaineering: up to 2.5 for waymarked routes and paths, 1.5 for huts, 2 for the ascent from the valley (2,000 m), 1.5 for prominence (3,000 m), 1.5 for the season (months with summit afternoons above −5 °C) and 1 for via ferratas, climbing and glaciers. OpenStreetMap is built by volunteers: where few things are mapped, a score can be lower than reality.
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Snow
At the summit, snow all year round. Month by month below, at different heights on the way up.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Summit4,194 msnow all year round | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month |
Halfway up2,623 msnow from October to June | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | No snow | No snow | No snow | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month |
Fiesch1,052 msnow from December to April | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | Snow on the ground all month | No snow | No snow | No snow | No snow | No snow | No snow | No snow | Snow on the ground all month |
Estimate for a normal year: average temperature and precipitation from NASA POWER, carried to each height, in a simple model of snow building up and melting. In a given year snow can come earlier or stay longer. It does not replace the local snow and avalanche bulletin.
Summit weather
Not a forecast: long-term averages (1991–2020), carried up to the summit. The orange line is where an average afternoon reaches 0 °C; above the dashed blue line it freezes even at dawn.
On an average July afternoon the summit reaches about 1 °C; on January nights it falls to about -27 °C. In 10 months of the year it stays below freezing at the top even in the afternoon. In July the 0 °C line climbs to about 4,410 m, above the summit: the top thaws on an average afternoon. Across the region, February is the driest month (69 mm) and August the wettest (165 mm).
| Month | Summit high °C | Summit low °C | Fiesch high °C | 0 °C line (m) | Rain & snow (mm) | Wet days | Sun h/day |
|---|---|---|---|---|---|---|---|
| January | -19 | -27 | 1 | 1,220 | 81 | 14 | 4.1 |
| February | -18 | -27 | 2 | 1,350 | 69 | 12 | 5.5 |
| March | -15 | -23 | 5 | 1,840 | 89 | 15 | 6.4 |
| April | -10 | -18 | 10 | 2,580 | 103 | 16 | 5.9 |
| May | -5 | -14 | 15 | 3,390 | 154 | 20 | 5.7 |
| June | 0 | -9 | 20 | 4,130 | 151 | 20 | 7.4 |
| July | 1 | -8 | 22 | 4,410 | 148 | 19 | 7.9 |
| August | 1 | -8 | 21 | 4,350 | 165 | 18 | 7.1 |
| September | -3 | -12 | 18 | 3,750 | 106 | 16 | 6.1 |
| October | -7 | -16 | 13 | 3,050 | 107 | 15 | 4.7 |
| November | -14 | -20 | 7 | 2,070 | 114 | 16 | 3.4 |
| December | -18 | -26 | 2 | 1,390 | 92 | 15 | 3.4 |
Estimate: the NASA POWER climate of a ~55 km cell (average height 1,854 m), adjusted to the summit by −6.5 °C per 1,000 m. Rain, wet days and sunshine are those of the region. Mountain weather changes fast — always check a local forecast. ★ = mildest months at the top.
Relief
Two cuts through the summit, 16 km long, from the 30 m Copernicus elevation model. True scale: no vertical exaggeration.
Average slope of the first kilometre from the summit. The orange petal is the steepest side.
Around the mountain
Counted around the summit in OpenStreetMap, the map anyone can edit. The satellite plate shows 14 × 14 km.
N
5 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 14 × 14 km, north up. Points © OpenStreetMap contributors.
A lift reaches Eggishorn at 2,869 m — just 1,325 m below the summit.
Berggasthaus Tschingelhorn (1,678 m), Tällihütte (1,951 m), Driesthütte (2,181 m), Baltschiederklause and 7 more
Bettmeralp - Bettmerhorn, Gletscherbahn Moosfluh, Fiescheralp - Eggishorn, Flesch and 3 more
Mürren/Schilthorn, Jungfraujoch Snow Fun Park, Aletsch Arena, Blatten Belalp and 2 more
Aletsch Panoramaweg, Oberaletschhütten - Oberaletschgletscher, Punkt 2586 - Fusshornbiwak, Z'Leng Fäsch - Fusshornbiwak and 5 more
Klettersteig Eggishorn, Rock Metal Climbing (B/C), Seilbrücke (B/C)
Schmadrigletscher, Hochfirn, Konkordiaplatz, Grosser Aletschgletscher and 23 more
Gletschertor, Platta, Moosfluh, Gletscherblick and 23 more
Alpina, Hotel Restaurant Stechelberg, Mittagshorn, Hotel Post and 81 more
11 path sections within 5 km, by SAC hiking scale (T1 easy walk … T6 difficult alpine).
OpenStreetMap is built by volunteers: a low number may just mean nobody has mapped it yet. Places © OpenStreetMap contributors (ODbL).
Photos
Recent years
Afternoon high at the summit (estimate). The first row is the reference, the 1991–2020 average in °C; the years show only the difference.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1991–2020 average | -19 | -18 | -15 | -10 | -5 | 0 | 1 | 1 | -3 | -7 | -14 | -18 |
| 2020 | +2.2 | +2.9 | +0.4 | +2.8 | +1.8 | −1.7 | +0.9 | +0.7 | +1.0 | −2.5 | +3.5 | −0.6 |
| 2021 | −1.4 | +2.2 | −0.3 | −1.8 | −2.5 | +1.0 | −0.6 | −0.9 | +1.7 | −0.4 | −0.2 | +1.2 |
| 2022 | +1.2 | +1.6 | +2.1 | +1.2 | +2.8 | +2.8 | +2.8 | +2.3 | −0.5 | +3.8 | +0.7 | +1.0 |
| 2023 | +0.2 | +2.6 | +2.9 | −0.7 | +0.3 | +1.1 | +1.6 | +1.4 | +4.0 | +3.1 | −1.1 | +1.8 |
| 2024 | +1.7 | +4.1 | +1.4 | −0.8 | −0.6 | −0.1 | +1.8 | +2.9 | −1.6 | +1.1 | +2.4 | +1.9 |
| 2025 | +1.7 | +2.4 | +1.4 | +2.7 | +0.5 | +4.1 | −0.8 | +1.4 | +0.7 | −0.2 | −0.1 | +2.4 |
+1 warmer than usual −1 cooler than usual
| Names, elevation, prominence | Wikidata (Q15293) · CC0 |
|---|---|
| Relief, 3D view, profiles | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Climate | NASA POWER, 1991–2020 · CC BY 4.0 |
| Around the mountain | © 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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