Mount Hekla is a mountain on Arcta, located at meridian 079 of quadrant three, with its summit above the atmospheric cloud layer (TOS: "The Gun on Ice Planet Zero, Part I").
Doctor Ravashol lives at the base of this mountain, which contains a Cylon garrison. At the top of the mountain is the Ravashol pulsar, which the Cylons use as a weapon against the Fleet, as well as a launch bay filled with Cylon Raiders directly behind the pulsar emplacement.
During the firing of the pulsar, the resulting sound waves cause avalanches. One such avalanche injures Ser 5-9 as Apollo's expedition climbs towards the intake valves for the pulsar located atop the mountain (TOS: "The Gun on Ice Planet Zero, Part II").