10 of Iceland's Longest Lava Tubes

Laufbalavatn lava tube system, around 5012 meters long

Surts-, Stefans- og Hulduhellir lava tube system, probably well over 5000 meters long

Kalmanshellir lava tube system, around 4012 meters long

Surtshellir-Stefanshellir lava tube system, around 3490 meters long

Surtshellir lava tube, around 1970 meters long

Idrafossar lava tube, around 1913 meters long

Vidgelmir lava tube, around 1584 meters long

Stefanshellir lava tube, around 1520 meters long

Hulduhellir lava tube, probably over 1500 meters long

Raufarholshellir lava tube, about 1360 meters long

Volundur lava tube, around 1108 meters long

Vorduhellir-Litli-Bjorn lava tubes, around 1100 meters long

Floki lava tube, about 1096 meters long

Buri lava tube, around 1025 meters long

Langiþrongur, um 1000 metrar

Flodhellir, um 982 metrar

Blami, um 913 metrar