Sadopaul · CC BY 4.0 · Wikimedia Commons
Mountain in Jeju, South Korea
Hallasan is a volcano in South Korea. Its summit stands 1,947 m above sea level. It is the highest point of KR. Its prominence — how far it rises above the highest saddle linking it to a taller summit — is 1,947 m.
From the lowest point within 5 km (661 m), it rises 1,286 m. The steepest side is the south face: 27° on average over the first kilometre. In places the ground near the top reaches 55° — terrain for climbers, not walkers.
The nearest town is Seogwipo, 12 km away at 69 m: 1,878 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
6.5/10
Difficulty to the top
Hike
Most path sections around the top are T1 on the SAC hiking scale.
Indicative only — never a safety assessment. Conditions change: ask local guides and check the forecast.
Ski score
—
No ski runs within 12 km in OpenStreetMap.
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.
Plan your visit
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Snow
At the summit, snow from December to May. Month by month below, at different heights on the way up.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Summit1,947 msnow from December to May | 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 | No snow | No snow | No snow | Snow on the ground all month |
Halfway up1,008 moccasional snow from January to February | Snow some of the time | Snow some of the time | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow |
Seogwipo69 mno snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow | No snow |
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 August afternoon the summit reaches about 15 °C; on January nights it falls to about -6 °C. In 4 months of the year it stays below freezing at the top even in the afternoon. In August the 0 °C line climbs to about 4,300 m, above the summit: the top thaws on an average afternoon. Across the region, January is the driest month (50 mm) and August the wettest (261 mm).
| Month | Summit high °C | Summit low °C | Seogwipo high °C | 0 °C line (m) | Rain & snow (mm) | Wet days | Sun h/day |
|---|---|---|---|---|---|---|---|
| January | -4 | -6 | 9 | 1,390 | 50 | 8 | 2.7 |
| February | -3 | -6 | 9 | 1,480 | 66 | 8 | 3.9 |
| March | -1 | -4 | 11 | 1,810 | 90 | 10 | 5.4 |
| April | 2 | -1 | 14 | 2,280 | 136 | 10 | 5.9 |
| May | 6 | 3 | 18 | 2,790 | 141 | 10 | 5.8 |
| June | 9 | 7 | 22 | 3,380 | 192 | 13 | 4.3 |
| July | 13 | 12 | 26 | 3,990 | 240 | 17 | 5.0 |
| August | 15 | 14 | 28 | 4,300 | 261 | 18 | 6.0 |
| September | 12 | 10 | 24 | 3,820 | 185 | 10 | 5.1 |
| October | 8 | 6 | 20 | 3,190 | 89 | 6 | 5.7 |
| November | 4 | 1 | 16 | 2,480 | 72 | 8 | 4.1 |
| December | -1 | -4 | 11 | 1,730 | 56 | 8 | 2.7 |
Estimate: the NASA POWER climate of a ~55 km cell (average height 54 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. Heights drawn 2× taller than lengths, so the shape can be seen.
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.
윗세오름2대피소
성판악코스, 관음사코스, 사라오름코스
구린굴 (Guringul), 병풍바위, 거린사슴전망대, 방아오름전망대 and 22 more
돈내코야영장, 상효수목원캠핑장, 관음사지구야영장
청아대리조트, 시온성민박, 칠십리민박, 유리성민박 and 19 more
33 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).
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 | -4 | -3 | -1 | 2 | 6 | 9 | 13 | 15 | 12 | 8 | 4 | -1 |
| 2020 | +1.8 | +1.8 | +1.2 | −1.1 | ±0.0 | +0.5 | −2.1 | +0.6 | −0.7 | −0.8 | +0.3 | −0.4 |
| 2021 | +1.2 | +2.0 | +2.2 | +1.1 | +0.8 | +1.3 | +1.5 | −0.2 | +1.1 | +1.2 | +0.3 | +1.0 |
| 2022 | ±0.0 | −1.4 | +0.9 | +1.0 | +0.9 | +1.0 | +2.3 | +1.0 | +0.4 | −0.7 | +1.7 | −0.9 |
| 2023 | +1.3 | +1.0 | +2.2 | +1.4 | +0.9 | +1.0 | +1.2 | +1.4 | +2.3 | +0.5 | +0.5 | +1.5 |
| 2024 | +1.9 | +2.6 | +1.2 | +2.3 | +1.1 | +1.2 | +1.6 | +2.5 | +4.0 | +2.3 | +1.8 | +0.2 |
| 2025 | +0.6 | −1.5 | +0.4 | +0.5 | −0.5 | +0.7 | +2.4 | +1.8 | +3.4 | +3.0 | +1.0 | +2.1 |
+1 warmer than usual −1 cooler than usual
Nearby
| Names, elevation, prominence | Wikidata (Q494645) · 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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