History
According to the legends, the Pillars of Utgard were merely the feet of the Utgard dragon, his jaws lying open beneath the waves, waiting for every ship that passed.[1] Thor's ship journeyed crossed the strait, heading toward the most dangerous part of the Pillars of Utgard: The Dragon's Jaws.[2] This cavern waterway was eventually blown to bits by Balder, allowing safe passage for the ship.[3]