Warsong Lumber Mill is the Horde base inside the Warsong Gulch Battleground.
It has three entrances. The main entrance is a long tunnel located in the front of the base. Within the ramp are Boots of Speed (a special battleground item) that will grant you greatly increased run speed for several seconds. The other two entrances either take you straight into the flag room or onto a balcony that overlooks it. These entrances are closer to the flag, but they also take longer to reach and have no special items along the way. Attached to the tunnel is a detour that leads to the top of the base. This path, while a great deal longer, is a good strategic point from which to view the entire flag room while avoiding detection.