Erebus Facility is an abandoned Mars facility. It was constructed to become the first base on Mars. However, when Mars City was constructed, the Erebus Facility was abandoned in Doom 3.
Two years after the Mars City incident in Doom 3, Erebus was reformed and restored to become the new base in Resurrection of Evil. Dr. Elizabeth McNeil was sent to Erebus Mining Facility to investigate. When the Artifact was located and the Marine touches it, Erebus Facility has the same fate as Mars City. Within a couple of minutes, the Erebus Mining Facility was destroyed and its personnel killed or zombified. The Marine must go to Hell again and destroy the man who's behind this.
Level 1: Main Excavation
The Main Excavation is the newest area in Site 1. It was first discovered when playing Resurrection of Evil. Also, it had one of the greatest discoveries: The Artifact. However, it released the forces of Hell once again.
Level 2: Dig-Site
The Erebus Dig-Site is one of the main areas in the Site 1 Caverns. Some discoveries include a portal, although this was not activated until Hell was released again. Also, Erebus Level 2 has many temples and traps, and the traps were activated in Hell's release.
Level 3: Erebus Labs
The Erebus Labs houses more Caverns, a Medical Station, and some Labs to do research on the Artifacts that were found in the Caverns. One of the best discoveries (before The Artifact was found), was the Artifact's research tablet, which has all the Artifact's secrets.
Level 4: Erebus Control
The Erebus Control is the facility that controls all of Erebus. It has its very own Common Area, many offices, and much more.
Level 5: Erebus Research
Erebus Research is another research sector in Erebus, plus it's Erebus' main Warehouse. Also, it has some Waste Tunnels that was found in Site 1, and brought to the Waste Tunnels for research. It is in the command of Dr. Cloud.
Level 6: Monorail Station
The Erebus Station is mainly just the main Monorail station in this part of Site 1 but its also a control station for Erebus as well. Plus it has an airlock that leads to the Martian Surface.