Seljavallalaug

Seljavallalaug is a long, narrow pool in a green valley under the Eyjafjallajökull volcano in south Iceland. Local people dug it in 1923 to teach their children to swim, and it is one of the oldest in the country. A warm spring feeds it, but the water stays only lukewarm and often green with algae — volunteers drain and scrub it just once a year. People walk 15–20 minutes up the valley for the setting; there are no staff and no showers.