Stefánshellir Cave
Stefánshellir is a large lava tube in the Hallmundarhraun lava field and forms part of the extensive Surtshellir–Stefánshellir cave system.
Together, Surtshellir and Stefánshellir extend for roughly 3.5 kilometres beneath Hallmundarhraun, a lava field formed shortly after Iceland was settled.
The cave is natural and unlit, and conditions can be demanding. Visitors should use a helmet, reliable lighting and suitable footwear.