Site 3: Analysis Facility
|Doom 3 maps|
Site 3: Analysis Facility is the twenty-fourth level of Doom 3. Where archaeological entities are brought to and where the research is done. This is the last level where the surface of Mars is visible.
Upon arriving at Site 3, the Player steps out of the elevator into a Hell-corrupted hallway and is almost immediately attacked by a swarm of demons including a Hell Knight. He defeats these demons, and heads into the Site 3 Hub where he battles Cacodemons and another Hell Knight. He then heads to the Freight Cart Terminal which will take him to the Caverns, and defeats more demons including yet another Hell Knight. However, the Freight Cart is still back at the entrance to the Caverns and the controls are in a restricted part of the base.
The Player goes to the Artifact Receiving area, where he's ambushed by an Arch Vile and its minions. After killing them, he goes through the lab section, fighting more enemies, including a couple of Revenants. Along the way, he finds Richard Davis' PDA which speculates that Mankind is descended from the Ancient Martians. Eventually, he arrives at Artifact Research where he finds four ancient stone tablets that the UAC researchers were studying. A video explains how the UAC built their teleporter devices using information from the tablets. It also goes into detail about the story the tablets tell of the Ancients' struggle against the demons, and how they used the Soul Cube to defeat the invaders.
More demons - including another Hell Knight - spawn. After the Player kills them, the door to a nearby locked office opens up, revealing a survivor - Dr. Pierce Rogers. Rogers is pleased that the Player has recovered the Soul Cube, saying it is the only way to stop this invasion. He gives the Player his PDA and a video disk of his discoveries, then tells him to get to the Caverns quickly.
Using Rogers' PDA, the Player gains entry to the Maintenance Area of the facility, and from there, fights his way to the Freight Control Tower. There, he recalls the Freight Cart back to Site 3, then returns to the Freight Cart Terminal. He boards the Cart and rides it to the entrance to the Caverns, where an elevator is waiting for him. He exits the Cart and gets into the elevator which will take him to Caverns Area 1.