Grænavatn (Greenlake) is a volcanic crater that got its name from its unusual green color. The color is due to a high level of sulphur in the water and its depth. The lake is only about few hundred meters in diameter. For a small lake it is quite deep, though, or 45 meters. This is visible as you stand by the brim, and you can see how the color changes by the shoreline where the lake gets deeper. Grænavatn is considered by geologists to be one of the most noteworthy geological phenomena of its kind in Iceland.
Translate
