Definitely one of the most famous and touristic places in Iceland is Geysir. Located on golden circle, not too far from the capital Reykjavik. Whoever visits Iceland usually goes to this place.
Originally I did not plan to go there this time again since I went there in 2018 already, plans changed due to extremely bad weather.
We planned to do a hike up the mountain where also a naturally hot river is located ( Valley of Reykjadalur) but cancelled it due to weather. We had hurricane-force winds even on ground level and horizontal rain.
Since the hike got canceled we had time for other things and decided to go to the Geysir again, its always cool to see this wonder of the earth again.
I think I don't need to explain how geysers work but here is a short description. Heat source warms up the water deep down underground to the point the pressure builds up and needs to release. Not much else to go than to the ground, this causes a water eruption you see on the photos. Then the cycle repeats.
There are several geysers on this ground but the strokkur is the only one that erupts after every 7 minutes on average. The other are quiet at the moment.
The photo below is the biggest one and erupts really high but does it very rarely.
Some other holes nearby.
If you ever go to Iceland then it is definitely worth a visit to this place.