From Halopedia, the Halo wiki
Kolaar Mountain, also known as Mount Kolaar, is a multi-peaked mountain in the state of Vadam in Yermo, Iruiru, Sanghelios. The mountain is covered by expansive groves of trees and the peaks are covered in snow.
It forms a part of Vadam keep, the foot of the mountain comprising its lower levels. It is also a centrally located stronghold; in times of war, its hardened rock and an underground river running beneath it ensured the survival of Vadam and its citizens from its historic assailants. The distance between Vadam Keep at the foot of the mountain and Vadam Harbor spans thirty miles. Kolaar Mountain is also of historic significance as the bearer of the Vadam saga. In the stone room of Vadam keep, deep within the mountain, the continuing Vadam saga is carved upon the walls. The Kolaar Manufactorum is a forge in Vadam likely based around the mountain and is named after it.
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