Snowbound

Snowbound is a multiplayer map in Halo 3. It is a winter-themed level with large Covenant bases, an underground tunnel network, and Fusion cores, strategically placed near the shotgun ( placed in the tunnels) and sniper. Several rock outcroppings are placed around half of the perimiter of the map, some weapons are strategically placed within the cover that the rocks offer. There are also bunkers protected by energy shields that stop all weapons, but let players pass through. Although, Spike Grenades can stick to the shield itself. There are also Automatic Turrets, which shoot players venturing outside the maps boundaries. It could be a new version of the Halo 2 map, Containment. However, a recent podcast by 1UP has shed more light on the maps layout and nature, and it is decidedly not a remake of any previous maps, and as such, among the three known maps, unique.
 * Weapons: Shotgun, Sniper Rifle, MA5C Assault Rifle, Battle Rifle, Automatic Turrets, SMG, Needler, Carbine, Spiker, Plasma Pistol.
 * Vehicles: Ghost.
 * Size and shape: Smaller and more symmetrical.

Below the bases are the spawns for the Spiker and the Plasma Pistol, as well as several grenades. On top of the bases are the Needler and Carbine spawn points.

Beneath the bases are tunnels that lead to a central room, and them further on to the other base. In this room is the Shotgun spawn, surrounded by fusion cores. Besides going to the bases, there are two ways out of this room, one which leads to the Ghost spawn, and another which leads to a narrow trench linking the two bases on the surface. Near each of the bases is a small cave where the Sniper Rifle spawns, once again surrounded by fusion cores.