A geologically young land, Iceland is located on both the Iceland hotspot and the Mid-Atlantic Ridge, which runs right through it. This location means that the island is highly geologically active with many volcanoes, notably Hekla, Eldgjá, Herðubreið and Eldfell. Iceland has many geysers, including Geysir, from which the English word is derived, and the famous Strokkur, which erupts every 5–10 minutes. After a phase of inactivity, Geysir started erupting again after a series of earthquakes in 2000.
With the widespread availability of geothermal power, and the harnessing of many rivers and waterfalls for hydroelectricity, most residents have access to inexpensive hot water, heating and electricity. The island itself is composed primarily of basalt, a low-silica lava associated with effusive volcanism as has occurred also in Hawaii. Iceland, however, has a variety of volcanic types (composite and fissure), many producing more evolved lavas such as rhyolite and andesite. Iceland has hundreds of volcanoes within approx. 30 volcanic systems active.