Reykjanes Peninsula is always a great area to visit with lots of interesting attractions. Gunnuhver is one of them. It is a hot spring in a bigger geothermal area, near the Lighthouse Reykjanesviti. It is the biggest mud pool in Iceland, 20 meters wide, with temperatures over 300°C. The area is on the Mid Atlantic rift and there are hot springs, mud pools, fumaroles and solfatara. – If you visit the area note especially that it is important to keep to the tracks as the area is highly active.
The hot spring gets its name from a female ghost the ended her days there some 400 years ago, or so they say. She had been a great nuisance until a priest set a trap for her and she fell into the hot spring. Her name was Gunna, thus Gunnuhver.