Foundry (location)

From Halopedia, the Halo wiki

For the Halo 3 multiplayer map, see Foundry; for the Halo Wars 2 campaign level, see The Foundry.
The Ark's central Forge from space.

The Foundry,[1][2] also known as the Forge,[3] is a colossal manufacturing facility located at the heart of an Ark installation, used to construct Halo ringworlds. Both Installation 00 and its older counterpart, the greater Ark, possessed one.[3] Installation 00's Foundry was home to a scarred planetoid that had been extensively mined by Forerunner machines, either to support the construction of the Ark or for potential replacement Halo installations.[4][5]


Design details[edit]

The Greater Ark as seen in Halo Mythos.  This artwork was also used in the Halo Encyclopedia (2022 edition).
One of the original twelve Gyre installations rising out of the Greater Ark's forge.

Foundries have been an integral component of both the Greater Ark and Lesser Ark installations, with a broadly similar design and function in both instances - with the primary difference simply being the sheer scale of the Foundry. For the Greater Ark, the Foundry was responsible for constructing the Senescent Array of twelve ringworlds, with the Foundry measuring a total of 30,000 kilometres in diameter. However, it was incapable of constructing the smaller, more powerful Halo installations designed as an improvement over the original rings, necessitating the construction of a second Ark.[6] The Foundry on the second Ark was 10,000km in diameter - and constructed the second Halo array of seven rings of the same diameter.

The Foundry at the heart of the Lesser Ark (or, Installation 00) takes the form of a circular machine lining the centre of the installation, with mineral-rich moon in the middle that is mined by Retriever Sentinels to provide the raw resources needed for Assembler and Excavator Sentinels to construct new Halos.[2][7] The planetoid is partially obscured by dense violet clouds.[4][5] The planetoid at the center of the Foundry was originally located within the Milky Way galaxy, but was moved through slipspace by the Forerunners in order to be mined.[8]

One of the installation's cooling stations.

In late 2552, the Foundry's central planetoid appeared to be approximately one third of Earth's dimensions, with a diameter of roughly 4,255 kilometers. It could have originally been substantially larger, since the gap in which it is located appears able to accommodate an object at least twice its diameter. Orange-red coloration can be observed in the fissures which dot the planetoid, indicating that it may have a molten internal structure.[4][5] The Foundry's rim is lined with multiple different biomes, including at least one snow/alpine biome hosting a Clarion facility,[4] and another desert biome hosting one of the access points to translocate from the Ark onto the surface of the Halo in the forge.[9]

The Foundry generates so much heat that the Ark requires multiple cooling stations to keep the installation inhabitable. At least two such systems span a snowy gorge; it is possible that the massive cooling systems cause this icy climate.[10]


Along with the Sentinel populations found around the Ark, the Foundry has an extra, albeit passive defense. It is equipped with a massive energy barrier, which can be raised through activating barrier towers to protect both the core and the Foundry from a possible Flood attack. The Ark's Citadel, a superluminal communications array and the control center of the entire Halo system, is included within the barrier's confines.[4][5]

The Prophet of Truth raised this barrier in 2552, either intentionally or accidentally. A small section of it was subsequently lowered by a joint UNSC-Sangheili assault force in order to stop Truth from activating the Halo Array.


The Foundry, as seen in 2552.

Human-Covenant War[edit]

Following the destruction of Installation 04, the Foundry began crafting a replacement. During a mission to Installation 00's Cartographer, 343 Guilty Spark appeared to recognize this while looking at a map of the installation, but was prevented from explaining what he had seen.[11] Shortly after the Battle of the Citadel, Installation 08 rose out of the Foundry and into space in an incomplete but nearly-finished state.[4]


After the destruction of Installation 08, the Foundry began constructing a second replacement for Installation 04, known as Installation 09. By the time of the arrival of the UNSC Spirit of Fire in 2559, the installation was almost complete.[12]

When the Banished arrived on Installation 00, they took over the Foundry to act as one of their bases. In order to destroy the Banished flagship Enduring Conviction, the smart AI Isabel fired Enduring Conviction's ventral energy projector into the Ark which resulted in the installation's Aggressor Sentinels destroying the carrier.[13] The subsequent launch of Installation 09 opened portals to the ring and the Spirit of Fire's forces were forced to attack the Banished base in the Foundry to stop them.[9]

During the Second Ark Conflict, the almost-complete Halo installation in the Foundry was discovered by Professor Ellen Anders who proposed launching the ring to the Soell system in order to send a distress beacon to alert the UNSC of their situation.[12] Following the destruction of Enduring Conviction, Anders launched the ring from the Foundry[13] and it subsequently entered slipspace en route to the Soell system.[14]


List of appearances[edit]


  1. ^ Halo 3, Terminal 3
  2. ^ a b Halo Wars 2, Phoenix Logs: The Foundry
  3. ^ a b Halo: Primordium, chapter 42
  4. ^ a b c d e f Halo 3, campaign level The Covenant
  5. ^ a b c d Halo 3, campaign level Halo
  6. ^ Halo: Silentium, String 3
  7. ^ Halo Encyclopedia (2022 edition), page 343
  8. ^ Halo: The Art of Building Worlds, page 32
  9. ^ a b Halo Wars 2, campaign level The Foundry
  10. ^ Halo 3, multiplayer map Narrows: Map description "Without cooling systems such as these, excess heat from the Ark's forges would render the construct uninhabitable."
  11. ^ Halo 3, campaign level The Ark
  12. ^ a b Halo Wars 2, campaign level Hold the Line
  13. ^ a b Halo Wars 2, campaign level Under the Dark
  14. ^ Halo Wars 2, campaign level Last Stand