The Great Geysir is located in the Haukadalur valley on the slopes of the Laugarfjall lava dome. Eruptions can typically shoot boiling water up to 60 m (200 ft) high. However, nowadays eruptions occur infrequently, and in the past they stopped altogether for many years.
The Haukadalur valley also contains the Strokkur geyser, located approximately 50 meters (160 ft) to the south. Geyser Strokkur is really active now: 10-12 eruptions per hour.