Iceland 
In numbers.
0.12m³/s
Average flow
estimate
May
Sep
Best months
149m
Elevation
The water at Tröllafoss, month by month
It roars from October to April.
The fullest months: from October to April.
- 0.2 m³/sJan
- 0.2 m³/sFeb
- 0.2 m³/sMar
- 0.2 m³/sApr
- 0.1 m³/sMay
- 0.1 m³/sJun
- 0.1 m³/sJul
- 0.1 m³/sAug
- 0.2 m³/sSep
- 0.2 m³/sOct
- 0.2 m³/sNov
- 0.2 m³/sDec
From about 0.07 m³/s in the lowest month to 0.24 m³/s in the highest. Best months to go, with plenty of water and pleasant days: May and September.
Estimate: the timing comes from rain, snowmelt and evaporation (NASA POWER, 1991–2020); the amounts from the river model of HydroATLAS (WaterGAP, 1971–2000). Dams upstream can change the real flow.
Waterfall of the Leirvogsá river, Iceland
Tröllafoss is a waterfall in Iceland.
Getting there.
- Mosfellsbærnearest town · 9.3 km in a straight line
- Parking 950 m awaynearest car park in OpenStreetMap, straight line
- Reykjavík Domestic Airport (RKV)nearest airport with scheduled flights · 21 km in a straight lineCar hire at RKV airport (Reykjavík)Discover Cars · Affiliate link↗
- May and Septemberbest months to go (estimate)
Plan your visit
Stay, explore and get there
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.
Seen from the sky.
8 × 8 km of cloud-free satellite image, with what OpenStreetMap knows around the falls.
N
2 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 8 × 8 km, north up. Points © OpenStreetMap contributors.
The line follows the river as mapped in OpenStreetMap; heights from the 30 m Copernicus model, which smooths narrow drops — the published height of the falls is the one above.
Around the falls the river drops 70 m in 3.5 km. Here the river runs about 16 m below the lower rim of its valley.
What is around.
- —viewpoints
- —waymarked walking routes
- 2car parks
- —swimming spots
- —picnic sites
- —toilets
- —information boards and visitor centres
- —bus stops within 1 km
- 1other named waterfalls within 4 kmHelgufoss
- —caves
- 1campsitesMosskógar
- 1hotels, B&Bs and huts within 6 kmHveramýri
- —restaurants and cafés within 3 km
Counted in OpenStreetMap, the map anyone can edit, up to 2 km around the falls (unless noted). A low number may just mean nobody has mapped it yet. © OpenStreetMap contributors (ODbL).
Towns nearby
- Mosfellsbær9.3 km in a straight line
- Reykjavík19 km in a straight line
- Kópavogur21 km in a straight line
- Seltjarnarnes23 km in a straight line
- Garðabær23 km in a straight line
Weather
The weather, month by month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon °C | 1 | 1 | 2 | 5 | 8 | 12 | 14 | 13 | 10 | 5 | 2 | 1 |
| Night °C | -3 | -3 | -2 | 0 | 3 | 6 | 8 | 8 | 5 | 2 | -1 | -3 |
| Rain & snow (mm) | 179 | 162 | 161 | 123 | 96 | 86 | 104 | 121 | 184 | 148 | 148 | 182 |
| Wet days | 21 | 20 | 20 | 17 | 16 | 16 | 17 | 18 | 20 | 18 | 19 | 21 |
| Sun h/day | 0.3 | 1.0 | 4.0 | 6.9 | 8.1 | 8.0 | 6.8 | 5.8 | 3.6 | 2.2 | 0.5 | 0.4 |
| Snow on the ground (cm) | 16 | 15 | 14 | 9 | 2 | 0 | 0 | 0 | 1 | 6 | 12 | 14 |
Long-term averages 1991–2020 (NASA POWER) for a cell about 55 km wide, with temperatures carried to the height of the falls (149 m) at −6.5 °C per 1,000 m. Not a forecast.
Photos
Through visitors' eyes.
Recent years
Wet years and dry years
Rain of each month as a share of the 1991–2020 average. A wet season above 100 % usually means a fuller waterfall.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020 | 134% | 89% | 98% | 125% | 116% | 145% | 82% | 144% | 117% | 49% | 103% | 83% |
| 2021 | 59% | 55% | 100% | 91% | 72% | 127% | 105% | 93% | 129% | 102% | 128% | 74% |
| 2022 | 136% | 94% | 183% | 73% | 101% | 120% | 129% | 127% | 68% | 68% | 54% | 29% |
| 2023 | 88% | 155% | 34% | 101% | 213% | 158% | 18% | 81% | 97% | 102% | 59% | 77% |
| 2024 | 89% | 67% | 60% | 77% | 139% | 110% | 128% | 109% | 62% | 85% | 113% | 121% |
| 2025 | 97% | 124% | 115% | 70% | 105% | 107% | 123% | 106% | 79% | 110% | 36% | 75% |
130% wetter than usual 70% drier than usual
Compare with the waterfalls nearby.
Tröllafoss
Iceland
- —Height
- 0.12 m³/sAverage flow
- May, SepBest months
About these numbers
| Names, height, width, river | Wikidata (Q4612764) · CC0 |
|---|---|
| River flow and catchment | HydroATLAS / RiverATLAS v1.0 (Linke et al. 2019) · CC BY 4.0 |
| Climate | NASA POWER, 1991–2020 |
| Relief, river profile, 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Paths, viewpoints, parking | © 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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