Triceratops were among the dinosaurs transported to the 1970s by Whitaker as part of Operation Golden Age. The Third Doctor and the Brigadier found one in the London Underground. Using flares, the Brigadier warded it away to give the Doctor time to plant explosives about the area. (TV: Invasion of the Dinosaurs)
Triceratops was among the species placed aboard the Silurian Ark to repopulate the Earth with after the catastrophe the Silurians incorrectly predicted had passed. In the 24th century, when the Eleventh Doctor and his companions came aboard the Ark, they used a Triceratops, nicknamed Tricey as a mount. Solomon later had the Triceratops killed to make an example out of it.
Another Triceratops was seen on Brian's postcard's picture of Siluria, indicating that the Ark had at least one other Triceratops specimen besides Tricey which was taken to Siluria by the Eleventh Doctor after he stopped the Ark from returning to Earth. (TV: Dinosaurs on a Spaceship)
Similar creatures edit
The planet Skaro was also home to creatures that resembled dinosaurs, specifically the Triceratops, but with only one horn. Normally peaceful herbivores, they would attack Daleks on sight. The Third Doctor and Finney used a herd of these to destroy a group of Daleks that had taken them to Skaro. (COMIC: The Planet of the Daleks)