The Mountains of Dhoom are a chain of peaks created during the Breaking of the World. During the Breaking, the volcano of Shayol Ghul, then an island, became the epicenter for the destruction wreaked by the Hundred Companions after the Dark One tainted saidin. New landmasses arose, and the Mountains of Dhoom formed during this time. The Mountains of Dhoom appear to encircle the northern polar regions of the world, and stretch right across the Westlands, the Aiel Waste, Shara and Seanchan. It is believed they even continue underneath the waves.