Thoronburg combat training facility
From Halopedia, the Halo wiki
The Thoronburg combat training facility is a former UNSC infantry training facility, located on a world with a shattered moon and a devastated surface. Possibly as a result of the cataclysm which resulted in these conditions, the UNSC was forced to abandon the facility, causing it to fall into disrepair.
The facility is the setting of the Halo 4 multiplayer map Pitfall, a remake of the Halo 3 map The Pit. As a remake, it is identical in layout to the UNSC Training Facility Bravo featured in The Pit, despite being a different in-universe location. Fictionally, these similarities may be attributed to standardization among UNSC training installations. One curious feature of Thornburg facility is its use of the post-war UNSC emblem as opposed to the original one. This may be due to a quirk in the War Games simulation (one that is repeated in all multiplayer maps, which should chronologically feature the original UNSC emblem) or indicate that the facility was abandoned after the Human-Covenant War.
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