Grjótagjá

The Grjótagjá (German: " crevice " ) is a cave with a small lake in Iceland.

It is located southeast of Reykjahlíð near Lake Mývatn directly on the here even visible on the surface geological fault zone between the continental plates of America and Europe. The geothermal activity causes heating of the underground lake.

Use as a bath cave

Already in the 18th century, the Grjótagjá should have served the wicked Jón Markusson as a residential and beach cave.

In 1938, she was rediscovered by English students as bathing cave.

Especially popular bathing was in the cave 1950-1977, with both locals and tourists.

From 1975 to 1984, the geothermal activity in the region grew strongly ( so-called Krafla fires), so that the water temperature rose to 60 ° C and the bathing was no longer possible. In addition, it was feared, the cave could collapse due to the increased earthquake activity. During this time the nearby Stóragjá was used as a " spare bathing cave ".

In spring 2004, the cave lake was released to swim, the temperature at the time was below 48 ° C. By May 2012, this has reduced to 44.6 °.