Unrevisitable Locations
Unrevisitable locations are locations that are accessed automatically during the storyline and inaccessible upon being left, thus, only visitable once in the entire play-through. Many unofficial guides and walkthroughs warn players of these locations beforehand, especially if they contain useful items.

Final Fantasy IV: The After Years

The player can revisit some areas in different Tales, but in some Tales they may be unrevisitable. Some locations become unrevisitable after the Point of No Return in a Tale, but reloading the player after completing the Tale may place them back at an earlier location, so areas that can be revisited upon reloading are not noted here.

In Ceodore’s Tale the player cannot re-enter the Adamant Isle Grotto and Mythril after leaving the area. In Rydia’s Tale the Underworld and all locations within become inaccessible after traveling to Agart. In Edge’s Tale the player visits the Dwarven Castle, Tower of Trials, Mount Ordeals and the Impact Crater with the members of the Eblan Four, and can only visit them in Edge’s Tale once.

In Porom’s Tale the locations visited in flashbacks – Kaipo, the Ancient Waterway, Mist and the Feymarch – cannot be revisited in the final part of the Tale. In Kain’s Tale, the Mist Cliff, Kaipo, Ancient Waterway and Damcyan cannot be revisited.

In The Crystals, the final tale, many cave areas are blocked off by meteor strikes or cave-ins or otherwise cannot be re-entered. These locations are – Underground Waterway, Devil’s Road, Mist Cave, Ancient Waterway, Antlion’s Den, Impact Crater, Mt. Hobs, Mount Ordeals, Adamant Isles Forest, Agart Mine, and Tower of Babil. Additionally the Red Moon is inaccessible outside of The Lunarian’s Tale.