Narnia is the fictional world visited in C.S. Lewis’s The Voyage of the Dawn Treader. Edmund and Lucy Pevensie enter Narnia again, this time alongside their cousin Eustace Scrubb.
The children join King Caspian X aboard the ship Dawn Treader for a voyage toward the eastern edge of the Narnian world. The expedition searches for seven lost lords who had been sent away during Caspian’s reign.
The alternative answers belong to other Lewis settings: Malacandra is the Mars-like world in Out of the Silent Planet, Perelandra is the planet of Lewis’s second space novel, and Charn is a ruined world connected with The Magician’s Nephew. These names are distinct from Narnia.