Greece
Satellite: Sentinel-2 cloudless 2017 by EOX (CC BY 4.0). Outline and points © OpenStreetMap contributors / Natural Earth. North up.
In numbers
64.2km²
Area
88km
Coastline
456m
Highest point
Kouvouli
3,138
People
26°C
Warmest sea
August
42km
To the mainland
When to go to Alonnisos
Best for the beach from July to September.
The sea is warmest in August (26 °C) and coolest in February (14 °C). Comfortable swimming (21 °C or more): from June to October.
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.
Greek island in the Aegean Sea and Municipality
Alonnisos is an island in Greece. It covers 64.2 km², with 88 km of coastline. Its highest point, Kouvouli, rises to 456 m. About 3,138 people live on it. The nearest mainland is 42 km away.
Getting there
- Skiathos Island National Airport (JSI)nearest airport with scheduled flights · 35 km in a straight lineCar hire at JSI airport (Skiathos)Discover Cars · Affiliate link↗
- FerriesVolos - Skiathos - Glossa - Skopelos - Alonnissos, Agios Konstantinos - Skiathos - Skopelos - Alonnissos, Alonnissos - Skopelos - Skiathos - Volos, Alonnissos - Skopelos - Skiathos - Agios Konstantinos
- 42 km from the mainlanddistance to the nearest continental coast
- From July 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.
On the island
What you find on Alonnisos.
- 55beachesKokkinokastro, Glyfa, Yialia and 52 more
- 2viewpoints
- 1lighthousesKokkino
- 4ferry terminalsDaily boat excursions, Patitiri ferry terminal, Flying Dolphin embarkation area and 1 more
- 10named peaksKouvoúli, Geladias, Xiropefko and 7 more
- 1dive centresAlonissos Seacolours
- 1campsitesROCKS
- 25hotels, guesthouses and apartments
- 60restaurants, 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.
Cross-checked with our atlases
Alonnisos in our other atlases
Everything Coastya, Peakyas, Lakeyas and Cascadyas know about what lies inside Alonnisos, each with its own numbers.
25beaches and covesCoastya
Beach with the warmest sea
25.8°C
sea in the warmest month · according to Coastya
25 beaches
on Coastya, the beach atlas
- Tourkonéri25.8°C
- Tzórtzi Gyalós25.8°C
- Tsoukália25.8°C
- Leftó Gyalós25.8°C
- Vrysítsa25.8°C
- Gyaliá25.8°C
- Chrysí Miliá25.8°C
- Spartínes25.8°C
17 more on CoastyaOpen Coastya ↗
The shape of the land.
On average the island stands 174 m above the sea. 61 % of it is below 200 m.
- 15 %0–50 m
- 46 %50–200 m
- 39 %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
- Patitírion1,628 people
Month by month
The weather on the island.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon high (°C) | 12 | 12 | 14 | 17 | 21 | 25 | 28 | 28 | 25 | 20 | 17 | 13 |
| Night low (°C) | 9 | 9 | 10 | 13 | 17 | 22 | 24 | 25 | 22 | 18 | 14 | 11 |
| Sea (°C) | 14 | 14 | 14 | 15 | 18 | 22 | 25 | 26 | 24 | 21 | 18 | 16 |
| Rain (mm) | 67 | 58 | 60 | 34 | 26 | 29 | 20 | 16 | 43 | 52 | 61 | 88 |
| Wet days | 10 | 9 | 8 | 6 | 6 | 4 | 3 | 3 | 6 | 7 | 8 | 10 |
| Sun h/day | 2.9 | 4.0 | 5.6 | 7.6 | 9.6 | 11.3 | 11.9 | 10.8 | 7.9 | 5.5 | 3.6 | 2.5 |
| Wind (km/h) | 21 | 21 | 18 | 16 | 13 | 13 | 14 | 16 | 16 | 17 | 18 | 21 |
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 | +0.6 | +0.8 | +0.6 | ±0.0 | −0.1 | −0.6 | −0.3 | +0.2 | +1.2 | +1.5 | +1.2 | +1.3 |
| 2021 | +1.9 | +1.8 | +1.5 | +0.9 | +0.6 | +0.5 | +1.9 | +2.2 | +1.0 | +0.2 | ±0.0 | +0.3 |
| 2022 | +1.1 | +1.0 | +0.5 | ±0.0 | +0.3 | +0.6 | +0.2 | +0.3 | +0.7 | ±0.0 | +0.7 | +0.9 |
| 2023 | +1.5 | +1.3 | +1.0 | +0.6 | −0.6 | −0.7 | +1.6 | +1.0 | +0.3 | +1.4 | +1.8 | +1.6 |
| 2024 | +2.1 | +1.3 | +1.4 | +2.1 | +0.1 | +1.2 | +1.6 | +1.5 | +1.7 | +1.8 | +1.5 | +1.4 |
| 2025 | +0.8 | +0.9 | +1.0 | +0.5 | −0.1 | +1.0 | +1.6 | +0.2 | +0.8 | +0.3 | +1.0 | +1.7 |
+1 warmer than usual −1 cooler than usual
Photos
Seen by visitors.
Nearby
More islands nearby.
About these numbers
| Names, area, population | Wikidata (Q647941) · 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.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers or canyons?
Same idea, other landscapes: field atlases built on open data, month by month, in seven languages.
beaches
Find your beach: sea temperature, sun and swimming month by month.Visit 
lakes
Every lake on Earth: water temperature, ice, depth and the shore.Coming soonVisit 
mountains
Every summit in 3D: summit weather, the 0 °C line, huts and trails.Visit 
waterfalls
Every waterfall: height, flow month by month and when it roars.Coming soonVisit 
islands
Every island from the sea up: size, sea temperature, ferries and 3D.You are here
rivers
Every river from source to sea: the journey, the flow and the basin in numbers.Visit 
canyons
Every canyon cut to scale: depth to the floor, rim and floor temperatures, trails and viewpoints.Coming soonVisit