A 55 meters deep volcanic crater lake in Grimsnes in South Iceland believed to be about 3000 years old. It is a very popular stop when travelling the Golden Circle. It is most likely that Kerið was originally a cone volcano that erupted and emptied its magma reserve, resulting in the weight of the empty magma chamber to eventually collapse, forming the crater. It’s part of a group of volcanic hills called Tjarnarhólar and it is now filled with water. The Kerið caldera is composed of red volcanic rock and is 170 meters wide, 270 meters across and 55 meters deep. The lake itself is fairly shallow and is truly striking in its beauty. With the opaque and aquamarine water contrasted by the red crater walls, Kerið offers a highly impressive scenery.