From Halopedia, the Halo wiki
For other uses of the term Charlie, see here.
Charlie Two was stationed in an underground UNSC base code-named "Crow's Nest" during the Battle of Earth, but contact was lost with Alpha Six after Crow's Nest's destruction. Its current status is unknown. It may include some of the Marines that made it out of the base through the caves underneath it and later regrouped at the Tsavo Highway.
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