Coastal Highway
Coastal Highway is an Achievement in Halo 3: ODST. It is unlocked when the player completes Template:Levelname at least on normal difficulty in Campaign Mode and unlocks the map Template:Levelname for Firefight. It is worth 50 Gamerpoints.[1]
It is represented by an olive circle, with the Marathon symbol imprinted in it, with a Waste Disposal Elephant (otherwise know as an Oliphant) in front of it.
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