- " He [Marty] looked out over the wide open prairie. It was just beginning to sink in — he was going back to visit the Wild West! / 'Hey, Doc,' he asked, 'you think I'll get a chance to ride a horse? I used to ride at summer camp. I was pretty good, too.' / Doc smiled at that. / 'I don't see why not.' "
- —From Back to the Future Part III by Craig Shaw Gardner (quote, page 33)
- " Marty read the horses' names on the stable doors [in Doc's livery stable] as he pulled on jeans, a workshirt, a pair of boots that actually fit, and a serape, just like the real Clint Eastwood always wore in those spaghetti westerns. 'Galileo', the first horse's sign read, then 'Archimedes', and 'Newton'. He grinned. No matter where Marty ran into him, you could always depend on Doc for some things. "
- —From Back to the Future Part III by Craig Shaw Gardner (quote, page 82)
They are also used for pulling vehicles such as chariots, wagons, or carriages.
After being sent to 1885 by a bolt of lightning, Doc set himself up as the town blacksmith. Part of his job involved shoeing horses. He also obtained three horses which he named Galileo, Archimedes and Newton.
On September 4, Doc and Marty tried to use six horses to pull the DeLorean time machine (which had a ripped fuel tank) up to 88 miles per hour, but failed. Later that day, they both rode horseback to save Clara when her panicked horse — which had been spooked by a snake — was about to pull her wagon buckboard over the edge of Shonash Ravine.
- Back to the Future Part II
- Back to the Future Part III
- Back to the Future Part III novelization (Doc's horses are named.)
- Back to the Future Part III (video game)
- Back to the Future: The Animated Series
- Back to the Future: The Card Game (Horse appears on Almanac cover.)
- Back to the Future: The Game
- Back to the Future: The Game - Episode 5: OUTATIME (Man shown riding horse on the screen of picture radio.)
- LEGO Dimensions (Non-canonical appearance)
- Back to the Future: Untold Tales and Alternate Timelines