From Halopedia, the Halo wiki
Tram station is a term used for the stations for the tram system on UNSC facilities, including the Orbital Defense Platforms or communications stations such as Reach's Gamma Station. The platform's personnel use the tram system to get around the station faster.
ODPs like Cairo Station house a tram line running throughout and tram stations near important locations such as the bridge and the exterior docking umbilicals near Starboard Shipping. In October 20, 2552, John-117 and Sergeant Major Avery Johnson used one to attend an awards ceremony, which was shortly interrupted by the start of the Battle of Earth.
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