Portal at Voi

From Halopedia, the Halo wiki

The Cartographer Building[1] is a Forerunner installation in the African Savvanah of Earth, near the city of Voi.

It is the Forerunner artifact revealed in the Halo 3 E3 2006 Trailer. There is a tremendous "storm" building over the desert near Voi[2], which is investigated by a Covenant Loyalist CCS-class Battlecruiser during the Second Battle of Earth. The UNSC military unit ONI Recon 111, that was assigned to shadow the battlecruiser, reports to Commander Miranda Keyes that the cruiser has "stopped...it's found something".

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