Kleifarvatn

Kleifarvatn () is the largest lake on the Reykjanes Peninsula in Iceland, situated in the southern part of the peninsula. It is located on the fissure zone of the Mid-Atlantic Ridge. The lake has no visible water coming in or going out as most of its water comes and leaves underground. The lake can be reached via a track, and there are two areas with high temperature that can be found not far from it: Seltún/Krýsuvík and another to the east. The lake's greatest depth is 97 m. After the 2000 Iceland earthquakes, the lake began to diminish, and 20% of its surface has since disappeared.
The novel "Kleifarvatn" by Icelandic writer Arnaldur Indriðason was named after the lake.