Director Jordan Peele stated in a podcast with Keke Palmer that Lake Mungo is one of the movies that scared him the most.
Despite the opening monologue, the film is a mockumentary, and is not based on real events.
The graffitied boulders, seen at 6:48 minutes, is a real location in Victoria, Australia called "Sister Rocks". It was named after the three Levi sisters who were among the area's first settlers during the mid 1800's gold rush. Opinions are divided over the graffiti - some say that the paint has ruined the natural beauty of the rocks, while others insist that the art serves as a unique guestbook and only enhances the attraction of this popular spot. Some of the graffiti dates back to the 19th century.
Although the film is fictional, Lake Mungo is a real place in New South Wales, Australia, and scenes in the film were shot there. Lake Mungo is a dry lake, and an important archaeological site. In 1968, the remains of a young Aboriginal woman were uncovered and she was nicknamed the "Mungo Lady". She was found to be ritually buried, and her bones were approximately 40,000 years old at the time of discovery. Mungo Lady is one of the earliest anatomically modern human remains discovered anywhere in the world. Five years later, another skeleton of around 40,000 years old was found at Lake Mungo, and named "Mungo Man".
Alice's phone, seen at 1hr 8mins, is a "Nokia 6600", released in June 2003.