Ernie Hudson stated that playing the character "Captain Munroe Kelly" is his personal favorite from his career.
The "diamonds" used for the scenes during the climax of the movie were actually Herkimer Diamonds borrowed from the Herkimer Diamond Mines of Middleville, New York. They are doubly-terminated (two-ended) quartz crystals that are found in only two places in the world. They were the only gems that would look enough like diamonds and be that large. As a kind of tribute, Tim Curry's character's first name is "Herkermer" (his character does not appear in the Michael Crichton novel upon which the movie was based).
Contrary to popular belief, the lava effects were not CGI; they were created in miniature using a methylcellulose mixture and composited into the final shots.
Executive producer and director Frank Marshall originally intended to use the computer work pioneered on Parque jurásico (1993) for the gorillas, but opted for models, as the computers weren't capable of reproducing hair.
Bruce Campbell auditioned for the role of Dr. Peter Elliot. He was given the small part of Charles Travis instead.