Stóragjá Fissure

Stóragjá is a wide crack in the lava at the edge of Reykjahlíð, part of the same rift system as the better-known Grjótagjá next door. A marked path leads to a gap where you climb down over rock and a fixed rope into a hidden chamber with a still, warm, blue-tinged pool. Locals bathed here for generations, but the water has cooled and testing found algae and bacteria, so it is now a place to look into rather than soak in.