Arcadia was created by Julie Langford, a botanist who gained much fame and recognition in the United States for her work. Arcadia is the source of oxygen and life in Rapture. The trees supply oxygen for the inhabitants to breathe and without it, life would cease to exist in Rapture. In addition to its reliability for life, Arcadia serves as a place of tranquility for the residents of Rapture. The peaceful scenery and lush plants lessen the stress of the otherwise contained Rapture. However, the spliced-up residents now use this place as a hub of ritual and scavenging. In the game, Jack has to stop a poisonous gas from entirely killing all of the flora in Arcadia by means of a special chemical.
The level was designed by JP LeBreton.