- California Doubling: The cave scene, in which Jim Morrison wanders out in the New Mexico desert, was shot at the Mitchell Caverns in the East Mojave Preserve in California. According to the tour guide there, Oliver Stone and the art dept. painted Indian petroglyphs at the site that wouldn't wash off. The state fined Stone and banned future film shoots at the caves.
- The Cast Showoff: Val Kilmer is quite skilled at fingerwalking: rolling something through and over his fingers. He has shown this in other movies (a coin in Billy the Kid, two coins while standing and walking in Real Genius, a poker chip in Tombstone and a crowbar in Top Secret!), and he shows it with drumsticks here.
- Dyeing for Your Art: Because the film was shot out of sequence, Val Kilmer had to carefully gain weight for Jim Morrison's heavier, later years so the flab was only noticeable on his belly, and could be concealed when he played Morrison as a younger man.
- Method Acting: Prior to production, Val Kilmer lived and breathed Jim Morrison for nearly a year, dressing in his clothes and hanging around his old haunts on Sunset Strip. Morrison biographer Jerry Hopkins says that he saw Kilmer one day when meeting Oliver Stone for lunch, using a payphone in the restaurant, and was so convinced that the first thought that entered his head was, "I'd forgotten how tall Jim was."
Trivia / The Doors (1991)