Location from Mass Effect by BioWare
The Collectors' station beyond the Omega 4 Relay — a Reaper-built nightmare at the accretion disk of a black hole, where the human colony abductions ended up.
The Collector Base sits on the accretion disk of a black hole and presumably survives proximity through Reaper technology that Shepard can only theorize about. It is unreachable — the Omega 4 Relay was believed impassable because no ship that went through ever came back. The debris field is the record of everyone who tried. The interior houses the Collector General, directly controlled by Harbinger. The harvested human colonists are stored in pods. The Human-Reaper — the prototype being built from their genetic material — occupies the deepest section. It is the destination of the Suicide Mission. The name is accurate about the odds. Shepard and crew went through anyway.
A massive space station with the same semi-organic interior as a Collector Cruiser — dark, wet-looking surfaces that are biological and mechanical at the same time, with the specific wrongness of Reaper-derived architecture. The debris field that fills the system is made of every ship that tried the Omega 4 Relay and failed. The Tartarus Debris Field dwarfs the station itself.
Also known as: Collector Base, The Base, Omega 4