Three Gates is a song included in the Halo 3: Original Soundtrack. It includes the songs Three Gates, Ascent, and Leonidas Returns. It can be heard during the level The Covenant and is the first movement of the Covenant Suite.
It starts with a low strings note, which is followed by the piano melody from the Halo 3 Announcement Trailer. Next comes the beginning melody of the Halo 3 E3 2007 Trailer, also a remake of the Halo 2 song Unyielding. At around 0:45 seconds, drums take over with a melody. Strings continue to play an accompaniment in the background. At 2:00 seconds, drums play a loud note, and Leonidas Returns, a re-recording of the song Leonidas from Delta Halo Suite, begins to play. Choir and strings are the main melody.
This section is played at checkpoint Alpha on the Halo 3 level, The Covenant during the first Hornet battle. Its title is likely a reference to the three shield towers that the allied forces must deactivate to reach Truth and the Citadel.
It runs for 4:35 seconds.
- The "Leonidas Returns" part of the track includes the second occurrence of the Delta Halo theme in Halo 3, the first being in "We're Done Here," the third movement of the Brutes suite, heard during the level Crow's Nest This theme can be heard in its' entirety in the Sacred Icon Suite, from approximately 1:53 to 2:23