Rushford Lake in New York is a real place. The history of the lake is also real. The remains of two towns rest at the bottom of the lake which was created by a dam which was completed in 1930.
Rebecca's cottage in the film was actually used as living quarters for nearly the entire first billed cast and the crew during filming. The garage to the next door cottage was initially used as the makeup and effects room, but was later moved to the basement of Rebecca's cottage.
Some of the locations where the movie says people drowned in the past, are real locations where drownings occurred.
Rick Kesler (the Reverend) had starred in several of Jay Woelfel's early shorts, as well as his first feature film. Kesler had quit the acting profession and became a real-life pastor, but he agreed to appear in the film as a favor to Woelfel .
Some of the cast & crew also slept at the Pink House in Wellsville, New York.