Were you looking for the Halo 2 level, Quarantine Zone (Level), or the location?

Quarantine Zone is an achievement in Halo 2 Vista and Halo: The Master Chief Collection. It can be earned by beating the level Quarantine Zone, on Normal, Heroic, or Legendary.

The Halo 2 Vista achievement is worth 30 Gamerpoints and is represented by a Flood Infection Form. This is also the same as the Halo: Combat Evolved Anniversary Popcorn.gif achievement.