The Battery Park Evacuation Center was one of many evacuation centers set up by E.M.A.T. to evacuate civilians to the New York mainland during the Ceph invasion and the Manhattan Virus outbreak. When the center was found by Alcatraz, it had been decimated by CELL forces, and the E.M.A.T. personnel there had either been slaughtered or had fled. The center consisted of thirteen E.M.A.T. medical screening tents along with decontamination showers, a guard tower, multiple external and internal walls, parking locations for vehicles, an isolated area (probably where carriers of the virus were taken for treatment), and a final processing checkpoint that led into the streets of lower Manhattan.
Battery Park was the first place where Alcatraz encountered CELL operatives. They were immediately hostile, had heavily fortified the center, and began a cleanup operation by burning deceased carcasses (within body-bags) that had been found on the site.