United States
Satellite: Sentinel-2 cloudless 2016 by EOX (CC BY 4.0). Outline and points © OpenStreetMap contributors / Natural Earth. North up.
In numbers
545km²
Area
223km
Coastline
406m
Highest point
Mount Lamlam
153,836
People
29°C
Warmest sea
July
2,655km
To the mainland
When to go to Guam
Best for the beach from January to May.
The sea is warmest in July (29 °C) and coolest in February (28 °C). You can swim comfortably all year (21 °C or more).
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.
Unincorporated territory of the United States of America
Guam is an island in United States. It covers 545 km², with 223 km of coastline. Its highest point, Mount Lamlam, rises to 406 m. About 153,836 people live on it. The nearest mainland is 2,655 km away.
Getting there
- Antonio B. Won Pat International Airport (GUM)airport on the island, with scheduled flightsCar hire at GUM airport (Hagåtña)Discover Cars · Affiliate link↗
- 2,655 km from the mainlanddistance to the nearest continental coast
- From January to Maybest 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 Guam.
- 113beachesAba Beach, Abong Beach, Ajmo Beach and 110 more
- 11viewpointsTwo Lovers Leap, Cetti Bay Overlook, Libugon Vista Point and 8 more
- 6marinasSumay Cove Marina, Agat Small Boat Harbor, Gregorio D. Perez Marina and 3 more
- 64named peaksMount Lamlam, Mount Jumullong Manglo, Mount Almagosa and 61 more
- 4waterfallsLower Talofofo Falls, Upper Talofofo Falls, Sigua Falls and 1 more
- 3castles and fortsFort Soledad, Fort Santa Agueda
- 2ruins and archaeological sitesPiti School
- 1dive centresMDA (Piti Shop)
- 3campsitesBeach camp, Beach camping, Inarajan pools camp
- 64hotels, guesthouses and apartments
- 188restaurants, 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
Guam in our other atlases
Everything Coastya, Peakyas, Lakeyas and Cascadyas know about what lies inside Guam, each with its own numbers.
29beaches and covesCoastya
1lakeLakeyas
6waterfallsCascadyas
Largest lake
0.65km²
Fena Lake
according to Lakeyas
Warmest lake
27.0°C
Fena Lake
surface water, warmest month · according to Lakeyas
Beach with the warmest sea
29.4°C
sea in the warmest month · according to Coastya
29 beaches
on Coastya, the beach atlas
- Uruno Beach29.4°C
- Tagachan Beach29.4°C
- Trinchera Beach29.4°C
- Ypao Beach29.4°C
- Gabgab Beach29.4°C
- Dadi Beach29.4°C
- NCS Beach29.4°C
- Outhouse Beach29.4°C
21 more on CoastyaOpen Coastya ↗
1 lakes
on Lakeyas, the lake atlas
- Fena Lake0.65km²
Lakeyas is coming soonOpen Lakeyas ↗
6 waterfalls
on Cascadyas, the waterfall atlas
- Talofofo Falls
- Tarzan Falls
- Malojloj Falls
- Namo Falls
- Cetti Falls
- Second Sigua Falls
Cascadyas is coming soonOpen Cascadyas ↗
The shape of the land.
On average the island stands 100 m above the sea. 96 % of it is below 200 m.
- 26 %0–50 m
- 70 %50–200 m
- 4 %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.
20 km
All outlines drawn to the same scale (Natural Earth and OpenStreetMap).
Towns on the island
- Dededo Village44,943 people
- Yigo Village20,539 people
- Tamuning-Tumon-Harmon Village19,685 people
- Tamuning19,685 people
- Mangilao Village15,191 people
- Barrigada Village8,875 people
- Santa Rita Village7,500 people
- Mongmong-Toto-Maite Village6,825 people
- Chalan Pago-Ordot Village6,822 people
- Yona Village6,484 people
- Apotgan5,224 people
- Agana Heights Village3,940 people
Month by month
The weather on the island.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon high (°C) | 28 | 28 | 28 | 28 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 28 |
| Night low (°C) | 27 | 27 | 27 | 27 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 |
| Sea (°C) | 28 | 28 | 28 | 28 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 28 |
| Rain (mm) | 82 | 51 | 42 | 47 | 62 | 97 | 197 | 315 | 278 | 231 | 136 | 69 |
| Wet days | 14 | 11 | 8 | 10 | 13 | 18 | 26 | 29 | 28 | 26 | 21 | 15 |
| Sun h/day | 7.5 | 8.2 | 8.9 | 9.6 | 9.6 | 9.2 | 7.6 | 6.1 | 6.1 | 6.6 | 7.7 | 7.9 |
| Wind (km/h) | 27 | 28 | 26 | 24 | 21 | 20 | 18 | 17 | 16 | 19 | 25 | 27 |
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 | −0.2 | −0.1 | ±0.0 | +0.3 | +0.2 | +0.4 | +0.3 | +0.7 | +0.8 | +0.8 | +0.7 | +0.7 |
| 2021 | +0.6 | +0.5 | +0.8 | +1.1 | +0.5 | +0.5 | +0.4 | +0.3 | +0.4 | +0.6 | +1.0 | +0.8 |
| 2022 | +0.6 | +0.4 | +0.6 | +0.3 | ±0.0 | +0.3 | +0.2 | +0.3 | +0.7 | +0.5 | +0.8 | +0.9 |
| 2023 | +0.6 | +0.8 | +0.9 | +0.6 | −0.1 | −0.2 | +0.2 | +0.2 | +0.3 | +0.2 | +0.4 | +0.7 |
| 2024 | +0.8 | +0.1 | +0.4 | ±0.0 | ±0.0 | +0.3 | +0.4 | +0.8 | +0.6 | +0.6 | +0.5 | +0.7 |
| 2025 | +0.9 | +0.7 | +0.6 | +0.6 | +0.5 | +0.6 | +0.3 | +0.4 | +0.5 | +0.4 | +0.5 | +0.6 |
+1 warmer than usual −1 cooler than usual
Photos
Seen by visitors.
About these numbers
| Names, area, population | Wikidata (Q16635) · 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, Lakeyas, Cascadyas — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; NOAA OISST; HydroLAKES (Messager et al. 2016) · CC BY 4.0, LakeTEMP (Korver et al. 2024) · CC BY 4.0 |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
The family
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