The convention center in Pomona, California was converted into the film's UFO Expo 9, and the interior of Witch Mountain was designed using photographs from a tour of NORAD's Cheyenne Mountain Complex.
Pusat konvensi di Pomona, California diubah menjadi film UFO Expo 9, dan interior Witch Mountain dirancang menggunakan foto-foto dari tur NORAD di Gunung Cheyenne .