We have never seen a geyser before, but this one is still IMPRESSIVE! We arrived around 830 in the morning in an effort to beat the tourists. When we arrived we were 2 of 7 people there (the convoy of 10 tour busses came about 45 minutes later).
Along the path to Strokkur you pass Litli-Geysir, steam vents and random holes in the earth with boiling water. It's quite a spectacle! At Strokkur, we waited the usual 3-7 minutes, and it erupted. The noise is quite loud and startling. We were a little underwhelmed UNTIL.... the next time Strokkur erupted it reached its zenith and we were left in awe. Each eruption is unique. We saw short sprays, very tall sprays, the blue bubble before it erupts, double eruptions, gurgling water & roaring of the water. Be careful, the spray from Strokkur changes easily with the wind. We thought we were safe, but ended up getting doused, but the water by that point wasn't scalding.
There are also other attractions to see here like the real Geysir and trails to more tectonic activity. The parking lot is free and there is a cafe/tourist info office/hotel across the street. The Geysir park itself accepts donations.
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