Portal at Voi

Were you looking for Porta, a Flood door? The Portal is a Forerunner complex in Africa on Earth, buried in the vicinity of Tsavo East National Park and the city of Voi. It was uncovered by the Covenant during the Second Battle of Earth.

It is the Forerunner artifact revealed in the Halo 3 E3 2006 Trailer. The Covenant excavated it shortly after they conquered Earth. According to messages from a Forerunner known as Librarian contained throughout the Ark, the portal on Earth was the last of numerous gateways constructed throughout the galaxy, and was buried shortly before the activation of the Halo rings.

The High Prophet of Truth landed the Forerunner Dreadnaught on the forerunner structure, and an unusual storm started up above it. The UNSC military unit ONI Recon 111 reported to Commander Miranda Keyes that the "cruisers above the crater have stopped...they've found something". The UNSC attempted to attack the structure, which was assumed by the UNSC to be the Ark. A small strike force in the city of Voi, consisting of SPARTAN-117 and some Marines and Factory Workers to clear a path for three Frigates and numerous Longswords.

Truth then activated the Gateway, opening a large Slipspace rift above the artifact which leaded to the Ark ,which is revealed to be outside the Milky Way galaxy. Truth and the rest of the Loyalist fleet retreat through the rift as the Seperatist fleet, along with the Arbiter, Miranda Keyes, and SPARTAN-117 pursued them to the Ark.

The Portal is estimated to have a diameter of 25,515 meters. Its centre is located between 3°15' and 3°20' South and between 38°30' and 38°35' East