Gullfoss rainbow: when and where to stand
Short answer: 6 Nov 2026: Best rainbow from Lower path at the edge of the falls, 10:10–16:15 (strongest around 16:10), if the sun is out.
Gullfoss drops in two steps into a deep canyon, and its spray rises out of the gorge in front of the viewing paths. Rainbows appear down in the canyon when the sun is behind you.
Fri 6 November 2026 · sunrise 09:23, sunset 16:48
Lower path: rainbow 10:10–16:15
Best rainbow from Lower path at the edge of the falls, 10:10–16:15 (strongest around 16:10), if the sun is out. Low water: thin spray, rainbows are small.
| Upper viewpoint by the visitor centre looking down and north-east into the canyon | A big, bright arc | 10:30–16:15 Best 16:10, low, down in the spray below you |
|---|---|---|
| Lower path at the edge of the falls beside the falls, in the spray | A big, bright arc | 10:10–16:15 Best 16:10, across the spray at eye level |
Hour by hour
| Time | Upper viewpoint | Lower path |
|---|---|---|
| 09:00 | ||
| 09:30 | ||
| 10:00 | ||
| 10:30 | ||
| 11:00 | ||
| 11:30 | ||
| 12:00 | ||
| 12:30 | ||
| 13:00 | ||
| 13:30 | ||
| 14:00 | ||
| 14:30 | ||
| 15:00 | ||
| 15:30 | ||
| 16:00 | ||
| 16:30 | ||
| 17:00 |
Plan it
The lower path along the canyon edge closes in winter. Summer has the most water and the biggest spray. A rainbow needs direct sun on the spray: on an overcast day there is none.
Through the year
| 15th of | Upper viewpoint | Lower path | Water |
|---|---|---|---|
| January | 11:45–15:25 | 11:45–15:25 | Low |
| February | 11:05–17:25 | 10:45–17:25 | Low |
| March | 11:00–19:00 | 10:45–19:00 | Low |
| April | 11:00–20:30 | 10:45–20:30 | Low |
| May | 11:05–21:35 | 11:00–22:00 | Low |
| June | 11:20–21:35 | 11:20–23:00 | High |
| July | 11:20–21:40 | 11:20–22:40 | High |
| August | 11:05–21:10 | 11:00–21:10 | Low |
| September | 10:50–19:25 | 10:35–19:25 | Medium |
| October | 10:40–17:35 | 10:20–17:35 | Low |
| November | 10:35–15:45 | 10:35–15:45 | Low |
| December | 12:40–14:05 | 12:40–14:05 | Low |
Gullfoss rainbows by month
Questions
What time is the rainbow at Gullfoss?
6 Nov 2026: Best rainbow from Lower path at the edge of the falls, 10:10–16:15 (strongest around 16:10), if the sun is out. The time moves through the year; pick your date above.
Which side of Gullfoss has the rainbow in the morning and which in the afternoon?
Upper viewpoint by the visitor centre: afternoons. Lower path at the edge of the falls: afternoons.
Why is there no rainbow at midday?
When the sun is higher than about 42°, the whole rainbow circle sits below the horizon. You can then only see it low down, in spray below you, if at all. In summer that rules out the middle of the day at most falls closer to the tropics.
When does Gullfoss have the most spray?
River flow is highest in June and July (Copernicus GloFAS, 2005–2024). More water means more spray and bigger rainbows, but also more mist hiding the falls.
How do you calculate the rainbow times?
A rainbow is a circle of about 42° around the point exactly opposite the sun. You only see the part of that circle that falls on sunlit spray, so it needs the sun behind you and lower than about 42° above the horizon. For every 5 minutes of the day we place that circle in the sky and check how much of it lands on the spray seen from each viewpoint.
Calculated from the sun's position at each viewpoint. The spray extent is an estimate for normal flow; wind pushes the mist around and can move the rainbow by a few degrees. Times are local (Atlantic/Reykjavik).