

Preceding the firing of the Halos in 97,445 BCE, the IsoDidact and 343 Guilty Spark visited the Ark's Cartographer to review the preparations for the Halo Array's deployment. The interiors of this Cartographer shared many architectural similarities with Alpha Halo's Cartographer shaft, although the two are considerably different in general layout. A Terminal was located within the wall near the activation switch for the energy bridge. Inside the wall was a deep chasm and an energy bridge allowing passage over it. Facing the desert on the other side, the Cartographer structure was protected by a large wall structure. One of the facilities was located on top of a massive spire structure, the map room itself lying in a wide open area giving a panoramic view over a massive waterfall and an ocean.

Installation 00, the Ark, was home to several Cartographers. The Cartographer's exterior on Installation 00. Omega Halo, the sole Halo ring present at the Ark at the time, was also projected in the hologram. The commanders conferred in a circle within an enormous hologram of the Ark while updates on the installation's status were provided through their ancillas. During the final weeks of the Forerunner-Flood war, this facility was the site of an emergency meeting between the Forerunner military leaders before the imminent Flood attack on the greater Ark. Like all installations involved with the Halos, the greater Ark possessed a Cartographer. In addition to the Installation 07 star map, Spark accessed a star map while using the Ark's Cartographer in order to pinpoint the Ark's exact location. This suggests that when prompted, a Cartographer can also act as a star map, not just an installation map. By inserting the Librarian's coordinate key, which had specifically pointed to Zeta Halo and with Rion Forge acting as a Reclaimer for the system when prompted, Spark caused the Cartographer to turn from a map of the installation into a star map pointing to a location on New Carthage which was located in an entirely different sector of the galaxy. When 343 Guilty Spark accessed the new Cartographer on Installation 07, he was also able to use it to access the installation's historical records. If a Cartographer facility is destroyed, a new facility is either constructed elsewhere or a different facility is repurposed to act as that installation's Cartographer due to how important the Cartographers are. A Forerunner armor's personal ancilla was able to link with the Cartographer and provide packets of information on the installation's past activities directly into the wearer's brain. Īn artificial intelligence is able to interface with the Silent Cartographer and, for example, set navigation points on the holographic projection. Due to their significance, the Cartographers are protected by multiple security measures. The Cartographer facilities on the various Forerunner installations differ in layout and design, though the primary map rooms on the Halo installations are buried within large structures housing a network of compartments and rooms. When activated, a Cartographer provides a real-time holographic map which can be used to navigate the massive expanse that is an installation, along with other relevant information such as pinpointing every room or location within the vast structure. Some installations contain a number of discrete Cartographer facilities. A central component of any installation of Forerunner construction, it is found on nearly all of their megastructures, such as the Halo Array and the shield worlds.
