The film, which is the Christian parable and sequel to 2005's hit The Chronicles of Narnia: The Lion, the Witch and the Wardrobe, will premiere in the summer of 2008.
Prince Caspian will be played by Ben Barnes.
Director Andrew Adamson returns for the new sequel along with the young quartet of British actors: Georgie Henley, Skandar Keynes, Anna Popplewell, and William Moseley.
He shared: "If we don't make [the film] now, we'll never be able to because they'll be too old."
Using a best-case scenario, it would take two years to make each movie, according to Rev Bob Beltz, director of special media projects for the billionaire media entrepreneur Philip Anschutz.
That would mean 12 more years and the last film would appear in 2017.
"They could end up holding the first screening of 'The Last Battle' just before my funeral service. That's about how long it may take us to do the whole series," quipped the 55-year-old Presbyterian pastor, referring to the seventh and final Narnia novel by the Christian apologist CS Lewis.
"Seriously, when we started seeing those first really big numbers roll in at the box office, that's when it hit me," said Beltz. "Some of us worked on this first movie for a very long time and now it seems like we may literally get to work on the Chronicles for the rest of our lives."
"Prince Caspian", which was first published in 1951, and is the second book in the seven-book series written by Lewis, finds the Pevensie siblings pulled back into the land of Narnia where a thousand years have passed since they left. The children are once again enlisted to join the colourful creatures of Narnia in combating an evil villain who prevents the rightful Prince from ruling the land.