From Halopedia, the Halo wiki
The Hellespont system is a planetary system formerly under the control of the Unified Earth Government, among humanity's Inner Colonies. Located close to Earth, the system as a whole was considered loosely controlled. Some time before 2552, the system was home to the colony worlds of Troy and Harmony. The former of which was considered to be the principal location of the system. However, both planets were glassed by the Covenant soon after in the Massacre of Troy. Some of the population was able to be evacuated secretly before the Covenant arrived.
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