Black Mesa Research Facility

Black Mesa Research Facility
Logo of Black Mesa
First appearance	Half-Life
Last appearance	Half-Life 2: Episode Two
Created by	Valve Software
Genre	First-person shooter
In-universe information
Type	Laboratory
Location	New Mexico, United States
Characters	Gordon Freeman, Barney Calhoun, Isaac Kleiner, Eli Vance, Wallace Breen, Arne Magnusson, Rosenberg, Gina Cross, Colette Green, Richard Keller

The Black Mesa Research Facility (also simply called Black Mesa) is a fictional underground laboratory complex that serves as the primary setting for the video game Half-Life and its expansions, as well as its unofficial remake, Black Mesa. It also features in the wider Half-Life universe, including the Portal series. Located in the New Mexico desert in a decommissioned Cold War missile site, it is the former employer of Half-Life's theoretical physicist protagonist, Gordon Freeman, and a competitor of Aperture Science. While the facility ostensibly conducts military-industrial research, its secret experiments into teleportation have caused it to make contact with the alien world of Xen, and its scientists covertly study its life-forms and materials. In a catastrophic event known as the "Black Mesa Incident", an "anti-mass spectrometer" experiment conducted on Xen matter causes a Resonance Cascade disaster that allows aliens to invade Earth, and is the catalyst for the events of the series.

Half-Life was critically acclaimed for its storytelling and level design. At the time, the integration of narrative in the form of interactive cutscenes and NPCs was considered groundbreaking for a first-person shooter.