Several EVPs can be heard throughout the movie.
An entire night's filming was omitted and re-shot.
Several more traditional horror movie elements were removed from the script during the shoot, including a lengthy sequence where the characters are stalked by an elderly man in a car.
The official poster art, created by Gina Territo, features a skeletal ghost holding a video camera as it floats out of a tunnel. On the side of the tunnel is a bit of graffiti which reads "Dodd was Here". This is a nod to the character of Dodd from David Cronenberg's adaptation of The Dead Zone (1983). Filming also took place in the same tunnel featured in this movie.
During the air horn scene, Anthony Lattuca is wearing a pair of 3D glasses handed out at select midnight screenings of Harry Potter and the Deathly Hallows: Part 2 (2011).