From Destinypedia, the Destiny wiki
Old Chicago is a human city located on Earth. As its name implies, Old Chicago may be from the Golden Age of humanity before the Collapse.  There is some degree of conflict on it as humanity tries to reclaim its former glory. The city is located in the middle of a big swamp. It is also where a Guardian found the Exotic Pulse Rifle Graviton Lance. A creature of unknown origin lies within the city, able to hunt Guardians.
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