VietnamCat Ba ArchipelagoIslandUNESCO World Heritage
Cát Bà Island
155 km² of land in the Gulf of Tonkin.
Satellite: Sentinel-2 cloudless 2016 by EOX (CC BY 4.0). Outline and points © OpenStreetMap contributors / Natural Earth. North up.
In numbers
155km²
Area
101km
Coastline
measured on a simplified outline
322m
Highest point
18,934
People
30°C
Warmest sea
August
3km
To the mainland
When to go to Cát Bà Island
Best for the beach from October to November.
The sea is warmest in August (30 °C) and coolest in February (19 °C). Comfortable swimming (21 °C or more): from April to December.
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 Haiphong, Vietnam
Cát Bà Island is an island in Vietnam. It belongs to Cat Ba Archipelago. It covers 155 km², with 101 km of coastline. Its highest point rises to 322 m. About 18,934 people live on it. The nearest mainland is 3 km away. It is part of a UNESCO World Heritage site.
Getting there
- Cat Bi International Airport (HPH)nearest airport with scheduled flights · 29 km in a straight line
- FerriesĐình Vũ - Cát Bà, Cát Bà - Long Châu
- 3 km from the mainlanddistance to the nearest continental coast
- From October to Novemberbest months to go (from 30 years of averages)
Plan the trip
Ferries, stays and things to do
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On the island
What you find on Cát Bà Island.
- 29beachesPublic Beach Cat Co 3, Public Beach Cat Co 1, Public Beach Cat Co 2 and 26 more
- 24viewpointsThe Forest Palace, Viewpoint and Ruins of Cannon Battlements, View on the bay and 21 more
- 1lighthouses
- 7ferry terminalsBen Beo, Viet Hai harbor, Cai Beo Terminal For Tourists and 4 more
- 1marinas
- 3named peaksNgu Lam peak, May Bau
- 1castles and fortsCannon Fort
- 2ruins and archaeological sitesBunker
- 1waymarked walking routesdi Ao Ech
- 4campsitesWoodstock Beachcamp, Camp for money and 2 more
- 141hotels, guesthouses and apartments
- 106restaurants, cafés and bars
Counted in OpenStreetMap, the map anyone can edit, inside the island's outline. A low number may only mean nobody has mapped it yet.
The shape of the land.
On average the island stands 77 m above the sea. 97 % of it is below 200 m.
- 41 %0–50 m
- 56 %50–200 m
- 3 %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).
Towns on the island
- Cát Bà30,000 people
Month by month
The weather on the island.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon high (°C) | 20 | 22 | 24 | 28 | 30 | 30 | 30 | 30 | 30 | 28 | 25 | 21 |
| Night low (°C) | 12 | 14 | 17 | 20 | 24 | 26 | 26 | 26 | 24 | 21 | 18 | 13 |
| Sea (°C) | 20 | 19 | 20 | 23 | 27 | 29 | 30 | 30 | 29 | 28 | 25 | 22 |
| Rain (mm) | 39 | 25 | 50 | 69 | 168 | 213 | 302 | 338 | 240 | 122 | 51 | 28 |
| Wet days | 5 | 6 | 10 | 10 | 18 | 23 | 24 | 25 | 19 | 12 | 7 | 5 |
| Sun h/day | 1.2 | 1.2 | 0.8 | 2.2 | 4.4 | 4.8 | 4.8 | 4.5 | 5.0 | 4.4 | 3.9 | 2.6 |
| Wind (km/h) | 14 | 14 | 13 | 12 | 12 | 12 | 12 | 10 | 11 | 13 | 13 | 14 |
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 | +0.9 | −0.1 | +1.1 | −0.2 | +1.2 | +0.4 | +0.7 | +0.5 | +1.6 | −0.4 | −1.0 | −1.0 |
| 2021 | −0.7 | +0.1 | +1.3 | +1.3 | +1.5 | +1.0 | +1.2 | +0.6 | +0.8 | +0.9 | −0.2 | +0.3 |
| 2022 | +0.9 | −0.6 | +0.3 | +0.1 | −0.8 | +0.5 | +1.2 | +1.0 | +1.0 | +0.1 | +0.7 | −0.1 |
| 2023 | −0.3 | ±0.0 | +1.2 | +0.5 | +0.7 | +1.4 | +1.8 | +0.6 | +0.5 | +1.0 | +1.1 | +1.2 |
| 2024 | +1.1 | +0.4 | −0.4 | +1.0 | +1.0 | +1.2 | +0.8 | +0.2 | +0.4 | +0.2 | +0.3 | −0.1 |
| 2025 | −0.4 | −1.6 | −0.5 | +0.1 | +0.5 | ±0.0 | +0.7 | +0.7 | +0.5 | +0.9 | −0.3 | +0.6 |
+1 warmer than usual −1 cooler than usual
Nearby
More islands nearby.
China
About these numbers
| Names, area, population | Wikidata (Q993402) · CC0 |
|---|---|
| Outline | Natural Earth · public domain |
| 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 |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
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