The only official Fallout game that directly takes place in Colorado is Fallout Tactics: Brotherhood of Steel (2001).

How Colorado appears in Fallout

  • Fallout Tactics: Brotherhood of Steel
    • The campaign follows a Midwestern Brotherhood splinter group that eventually operates in and around Colorado , especially the Cheyenne Mountain / Vault 0 area.
* Colorado is key to the main plot because the supercomputer called **the Calculator** is housed in **Vault 0** , located in Cheyenne Mountain.
  • Mentioned but not main setting
    • Denver, Colorado is referenced in Fallout: New Vegas – Lonesome Road as a ruined city known as the “Dog City,” but you never actually visit it in‑game.

So if you’re asking “what Fallout game takes place in Colorado” , the answer is Fallout Tactics: Brotherhood of Steel , with later games only referencing Colorado rather than using it as the primary playable setting.

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