Geysir - Strokkur (Iceland)
In Geysir (from which the name of this natural phenomenom is derived) you will find 2 geysers. Geysir erupts up till 80m high but only twice a day and at irregular moments. However near Geysir you will also find Strokkur which erupts with a 20m high jet of water every ten minutes. As soon as the pressure gets too high, an azure bubble develops and bursts shortly after.