Black Mesa Research Facility

A badass research facility located in New Mexico. After a cataclysmic disaster in Sector C, Gordon Freeman is left to fight off retarded zombie alien things and other creatures. The Hazardous Environment Combat Unit (HECU) is sent in to kill anything and everything remaining, while the Black Ops are sent in to arm a nuclear device. This event leads to the Seven Hour War, which destroys most of the world's population, and leads to the events in Half-Life 2.