The Light House featured in the film and on the poster is the Point Arena Light House, located on one of the furthest West points of the Continental United States near Manchester, CA. The house in the film was a shell built by the production team and was torn down after filming. The only permanent structures near the light house are some vacation rental units, formerly Coast Guard barracks, and the Light House Keeper's residence which is now a museum maintained by local volunteers. The light house has recently undergone renovations and is open to the public.
When Daniel is making phone calls to locate his friend, the phone number that he leaves on the answering machine is 555-2368. That phone number is the same as the one used in Ghostbusters (1984) in their TV commercials. This phone number was also the phone number used in When a Stranger Calls (1979); Carol Kane's character Jill Johnson gives Police Sargent Saggert a phone number of where she is babysitting. The above number: 555-2368, was the number she gave to the Sargent when she was speaking to him on the phone.