The interior ship shots were filmed in two separate sound stages at Warner Bros. studios in Burbank, California, one in which the ballroom set was built "right-side-up," the other where the identical set was built upside-down.
Dylan Johns (Josh Lucas) jogging on the deck of the ship during the beginning credits the evening before the ship capsizes, pays homage to the original film, The Poseidon Adventure (1972). In it, James Martin (Red Buttons) jogs on the deck of the ship before the night of capsizing. Mr. Martin starts off by taking a deep breath at the deck railing before starting off, and Dylan ends his jog at the deck railing. Both wear a full jogging suit, which are both the same color.
The original cut of the film was 123 minutes long, nearly 25 minutes more than the theatrical release. About twenty minutes of the deleted scenes are set before the wave hits the ship. These scenes include Maggie and Connor visiting the bridge, where the Captain and Gloria reveal their affair, a scene where we get more information on the Valentin/Elena situation, and one scene where Valentin watches Gloria practice before her evening performance. Most of Josh Lucas's character's background was removed, just like the conflict that was meant to be taking place between him and Maggie throughout their escape. These drastic changes probably were made after test screenings, but Wolfgang Petersen had final cut at that time. Petersen himself later defended the changes in interviews, because they made the movie faster and the disaster happens earlier. Petersen never expressed any intention of releasing the original cut or creating an Extended Version for Blu-ray, therefore it is reasonable to assume, that this shorter theatrical version, is in fact, his preferred Director's Cut.
Lindsay Lohan turned down the role of Jennifer Ramsey, that went to Emmy Rossum. This is the second time Rossum has taken a role originally meant for Lohan, the first time was for The Day After Tomorrow (2004).
In the film's trailer, Christian and Jennifer are seen talking about the current situation with Jennifer's father in the nightclub. This scene doesn't appear in the final cut, along with eight other scenes in the trailer.
The movie is set on New Year's Eve, and singer Fergie is doing a rendition of "Auld Lang Syne". Fergie is a member of the popular group "The Black Eyed Peas". Black-eyed peas are most commonly associated with, and eaten for good luck on, New Year's Eve.
The trivia items below may give away important plot points.
One set of similarities between the Poseidon and the original Poseidon Adventure has to do with the number of people trying to reach safety, the number who are killed, and their manner of death. Both movies had ten people trying to reach safety, with six making it. Stewards Acres (Roddy McDowell) in the Poseidon Adventure and Marco (Freddy Rodriguez) in Poseidon are both killed falling down shafts. Linda Rogo (Stella Stevens) in the Poseidon Adventure and Lucky Larry (Kevin Dillon) in Poseidon are both killed in falls when the ship shifts. Belle Rosen (Shelly Winters) in the Poseidon Adventure and Elena Morales (Mia Maestro) both die after the swim through the passageway, Belle by a heart attack and Elena by drowning caused by a head injury. And finally, both leaders of the groups sacrificed their lives to save the other; Rev. Scott (Gene Hackman) in the Poseidon Adventure by falling to his death after shutting off the steam that was blocking the escape, and Robert Ramsey (Kurt Russell) in Poseidon who drowned after reversing the thrusters.