From Halopedia, the Halo wiki
Windward is a Halo 3: ODST Firefight map, based on the campaign level NMPD HQ. Players initially spawn with a Sniper Rifle at the start of the round, but only ammunition can be found on the map. All players respawn with SMGs. The Special Enemy of this map is the Banshee, which spawns at the beginning of every wave and 2 Missile Pod Turrets with which to shoot it down.
Players start in a central building on the second floor. When they leave this room, they will enter a hall with stairs in the middle. On the other side of the hall there is a room with two med-kits. If you go downstairs, you will find two med-kits on each side of the hall (making it four med-kits in the central building). Should you take the doors in the lower hall, you will enter a small room with doors that lead on the left and right ledge. In the middle of this small room is a rocket launcher pack with two rockets.
Exterior/ledges, courtyard and tunnels
Enemy spawn points
Enemies can enter the playing field by a number of ways: Phantoms (which land on the pads or in the middle of the courtyards) or from the "monster closets" (shielded doors that the player can't enter). When the bonus round begins, the grunts can come from the roofs of the surrounding building or from the mentioned "monster closets". Enemies which appear on this map are: Brutes (all forms and ranks), Grunts, Jackals (a Jackal sniper can appear as well, but most of the time they are equipped with carbines or shields), Drones (shielded variant is present as well), Hunters and Brute-piloted Banshees.
Score over 200,000 total points on this map to unlock the Firefight: Windward achievement worth 10 gamerscore. This can be obtained online or solo on any difficulty, making it a rather easy achievement to obtain.