grjotagja cave - geothermal hot spring, lake myvatn, northern iceland

grjótagjá cave lake myvatn iceland grjotagja rock landscape travel stream nature lava mývatn geothermal hot spring krafla volcano game thrones jon snow wildling ygritte fault lines autumn barren desert game tourism tourist attraction visitor heated molten magma icelandic volcanic fall october water steam pool tundra stunning magnificent beautiful sight sightseeing impressive