Trivia: At the end of the film, the police officer advising Beatty and Voight to go away and not to come back is James Dickey, the screenwriter and author of the book the film is based on.
Trivia: The scene where Belle (Shelly Winters) dives into the water was actually rehearsed by having her jump into the water. She decided to dive in while filming the scene and that take was used.
Trivia: During the filming of one scene in a native village, Klaus Kinski hit one of the crewmen over the head with his sword, almost killing him. The man survived because he had a helmet on.
Trivia: The space ship "Valley Forge" from Silent Running was re-used in one episode of the television series "Battlestar Galactica" (1978-1979). It was called the "agro-ship," used to grow food for the colonists.
Trivia: Anne Bancroft, who plays Lady Jennie Churchill, was only 10 years older than Simon Ward, who plays her son.
Trivia: This film marked the on-screen debut of Woodstock.
Trivia: Hywel Bennett (Duckworth) doesn't have a single line of dialogue in the film.