Deildartunguhver, located in the lush valley of Reykholtsdalur in the Borgarfjörður district, is Europe's most powerful hot spring, yielding up to 180 litres (about 50 gallons) per second of 97 °C hot water. A conservation law was passed to protect the hot spring as it is the source of hot water for the neighboring towns of Borgarnes and even Akranes, traveling through a well insulated pipe, up to 64 kilometers long . The steam clouds rising up from the hot spring are surely impressive especially in cold winter days. Throughout the years, locals have used this hot spring to their advantage, for example by piping hot water to their houses for heating and bathing, but also to heat up greenhouses for cultivation of decorative flowers, vegetables and even tropical fruit.
Next to the hot spring is the Krauma Geothermal Bath Resort and spa, where hot water from Deildartunguhver is used to create several hot water pools for bathing at different temperatures, as well as steam baths. There are changing rooms with lockers at Krauma as well as showers, but before entering the pools, visitors are required to take a shower and wash carefully. Due to the constant flow of natural clean hot water, no extra chemicals like chlorine are needed for disinfection. Krauma also hosts a restaurant, conveniently located for those exploring the many sites the Borgarfjörður district has to offer. Deildartunguhver and Krauma are located close to the junction of road 50 Borgarfjarðarbraut and road 518 Hálsaseitarvegur just north of the tiny hamlet of Kleppjárnsreykir about 1,5 hour's drive from Reykjavik.