The wall represents possible alternate/future timelines which Frost saw in his flashforwards. Frost metaphorically refers to it — as well as other similar diagrams, such as one represented by domino chains — as a "Garden of Forking Paths". ("The Garden of Forking Paths") The wall was located in Building 7 of an abandoned Army depot at 423 Ingres Street, 46 miles northeast of Antelope Valley. ("The Garden of Forking Paths")