By Martin O'Donnell and Michael Salvatori.
From Halo 3 (20079/25/2007).
Duration: 0:47.

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Read wiki commentary.

Tracks that reference Three Gates:

from Fandom:

• Checkmate (Should I use Stalemate instead since there's already a song called Checkmate?) by Noisemaker

Wiki commentary for Three Gates:

Quasar Nebula: wiki editor

Bit of a weird case! Halo 3's soundtrack contains many tracks with multiple movements; the "containing" audio tracks themselves are not given names. Three Gates (0:47) is the first movement in a three-parter, followed by Ascent (1:15) and Leonidas Returns (2:33). The durations of these segments are marked in the album booklet.

The streaming release, however, only uses the first movement from each audio track as the title for that entire track; all three movements above sum to about 4:35, matching the streaming release, itself just titled "Three Gates".

Also, the album booklet presents its tracks (across two discs) mostly structured by in-game level name. Three Gates is part of "The Covenant" (as are nine other titled movements).