North Korea
Satellite: Sentinel-2 cloudless 2016 by EOX (CC BY 4.0). Outline and points © OpenStreetMap contributors / Natural Earth. North up.
In numbers
61.4km²
Area
102km
Coastline
491m
Highest point
24°C
Warmest sea
August
4km
To the mainland
When to go to Sinmi-do
Best for the beach from August to September.
The sea is warmest in August (24 °C) and coolest in February (1 °C). Comfortable swimming (21 °C or more): from July to September.
Averages 1991–2020. Sea: NOAA OISST, the water within 35 km of the coast. Air, rain and sun: NASA POWER. Best months weigh warm afternoons (23–30 °C), sea of 24 °C or more and few wet days.
Island in North Korea
Sinmi-do is an island in North Korea. It covers 61.4 km², with 102 km of coastline. Its highest point rises to 491 m. The nearest mainland is 4 km away.
Getting there
- Dandong Langtou International Airport (DDG)nearest airport with scheduled flights · 72 km in a straight lineCar hire at ICN airport (Seoul)Discover Cars · Affiliate link↗
- 4 km from the mainlanddistance to the nearest continental coast
- From August to Septemberbest months to go (from 30 years of averages)
Plan the trip
Ferries, stays and things to do
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.
Cross-checked with our atlases
Sinmi-do in our other atlases
Everything Coastya, Peakyas, Lakeyas and Cascadyas know about what lies inside Sinmi-do, each with its own numbers.
2beaches and covesCoastya
Beach with the warmest sea
24.1°C
Taegiŭl-p’o
sea in the warmest month · according to Coastya
The shape of the land.
On average the island stands 89 m above the sea. 88 % of it is below 200 m.
- 43 %0–50 m
- 45 %50–200 m
- 12 %200–500 m
Share of the island's area in each altitude band, from the Copernicus DEM (30 m, read at 30–240 m on large islands).
Size, for real
Next to islands you may know.
10 km
All outlines drawn to the same scale (Natural Earth and OpenStreetMap).
Month by month
The weather on the island.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon high (°C) | -2 | 0 | 5 | 12 | 18 | 22 | 25 | 26 | 23 | 17 | 9 | 1 |
| Night low (°C) | -7 | -6 | -1 | 5 | 11 | 17 | 21 | 22 | 18 | 11 | 3 | -4 |
| Sea (°C) | 2 | 1 | 2 | 7 | 12 | 17 | 22 | 24 | 23 | 18 | 12 | 7 |
| Rain (mm) | 7 | 20 | 24 | 57 | 89 | 110 | 282 | 254 | 94 | 56 | 51 | 16 |
| Wet days | 2 | 3 | 3 | 6 | 9 | 11 | 18 | 16 | 9 | 7 | 6 | 4 |
| Sun h/day | 5.4 | 5.9 | 7.1 | 7.2 | 7.4 | 6.1 | 3.9 | 5.3 | 6.6 | 6.3 | 4.9 | 4.9 |
| Wind (km/h) | 19 | 18 | 17 | 16 | 14 | 12 | 13 | 13 | 14 | 16 | 19 | 20 |
Averages 1991–2020 for the ~55 km NASA POWER cell over the island; the sea from NOAA OISST.
Recent years
Warmer and cooler years at sea.
Each month's sea temperature compared with its 1991–2020 average, in degrees.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020 | −1.3 | −0.8 | +1.3 | +1.0 | +0.6 | +0.8 | +0.6 | −1.5 | +0.2 | +0.5 | +0.1 | −1.6 |
| 2021 | −2.2 | −1.0 | +0.4 | +1.0 | +1.5 | +1.0 | +1.1 | +1.0 | +1.1 | +0.6 | −0.1 | −1.2 |
| 2022 | −1.9 | −1.0 | +0.6 | +1.6 | +2.1 | +1.2 | +1.4 | +0.9 | −0.2 | −1.7 | −1.2 | −3.0 |
| 2023 | −2.1 | −0.8 | +1.1 | +1.9 | +2.3 | +2.4 | +2.0 | +3.0 | +1.9 | +0.2 | −1.5 | −3.4 |
| 2024 | −1.6 | −0.3 | +1.4 | +3.0 | +3.4 | +3.2 | +1.7 | +3.0 | +2.9 | +1.4 | +0.2 | −2.0 |
| 2025 | −1.2 | −0.7 | +0.7 | +0.8 | +1.1 | +1.5 | +1.6 | +2.1 | +1.6 | +0.6 | −1.7 | −2.4 |
+1 warmer than usual −1 cooler than usual
South Korea
About these numbers
| Names, area, population | Wikidata (Q846115) · CC0 |
|---|---|
| Outline | © OpenStreetMap contributors · ODbL |
| Sea temperature | NOAA OISST v2.1 · 1991–2020 |
| Climate | NASA POWER · 1991–2020 |
| Relief, 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Beaches, ports, lighthouses, trails | © OpenStreetMap contributors · ODbL |
| Towns | GeoNames · CC BY 4.0 |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Beaches, mountains, lakes and waterfalls | Coastya — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; NOAA OISST |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
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