Rich in active gases or metals — a strong mineral character.
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
SoufreSulfuresSulfates
Kúalaug is a secluded natural hot spring pool in Biskupstungur, a farming district in the south of Iceland's Golden Circle region, between the Geysir geothermal field and the Þingvellir rift valley. The pool sits in an unassuming pastoral setting — open fields, distant mountains, the wide Icelandic sky — where the absence of infrastructure amplifies the sense of encountering the earth's heat in its most direct form. The sulfurous water reaches 38 °C, comfortably warm against the cool northern air, with the acidic pH of 6.5 typical of Iceland's volcanic spring chemistry. There are no changing facilities or entrance fees; the ritual is entirely unmediated. Known mainly to locals and those who seek out Iceland's lesser-publicised natural pools, Kúalaug rewards the traveller who prefers solitude and raw landscape over the polished experience of the country's more famous thermal destinations.
Insider tip — Kúalaug is a geothermal pool in Biskupstungur parish, part of the Geysir-Gullfoss corridor of the Golden Circle, one of Iceland's most intensely geothermally active regions. The spring surfaces near the boundary of the Haukadalur field, fed by the same shallow volcanic heat source that powers Strokkur. The pool offers a quieter soaking alternative to the crowded Geysir visitor area, accessible via a short walk from a farm road. Bishops' Tongue — the literal translation of Biskupstungur — was an important medieval ecclesiastical district, and warm springs were used for bathing and washing by the church community throughout the medieval period.
