From Halopedia, the Halo wiki
Universe and lore
The map is set within one of the many canyons on the surface of Installation 07. Set into the side of a high cliff, this canyon hosts two beam emitters, and various Forerunner nodes and beacons. Following the ring's fragmentation during Battle for Zeta Halo, the 511th Infantry Division from the UNSC Infinity have established a base of operations in the canyon, and set up equipment to survey the fragment of the ring. While fighting off Sentinel patrols and evading the increasingly frequent scouting runs of Banshee talons, the survivors attempted to make contact with other UNSC forces that might be within comms range.
The following are locations on the map that are so named on the player's heads-up display during gameplay:
The map was first shown unnamed in the A New Generation trailer, and was eventually shown in more detail with hints to its setting in the Halo Infinite Multiplayer Overview trailer. Finally, in a Canon Fodder post on Halo Waypoint, Fragmentation had its name revealed and further story details divulged. The map is playable in the second Halo Infinite multiplayer preview.
In Capture the Flag once a flag is captured the scoring team's beam emitter will fire.