Illustrated Guide to the world of Spira (FFX and FFX-2)/Hidden Dungeons
There are 14 dungeons in the world of FFX and FFX2. Dungeons in Spira vary very little in style, most of them look like ancient stone temples with a hint of Ancient Egyptian stonework. Notable exceptions are Bevelle Cloister, Bevelle's underwater maze and the cave dungeons on Omega Ruins and the Den of Woe. Mt. Gagazet has a very unique cave dungeon with some parts submerged under water.
Palace Dungeons
editBevelle - Bevelle Cloister Dungeon - Via Infinito
editCan be explored only on Final Fantasy X-2. The dungeon is located at the right side of the Temple, 1st floor. It has several game goodies and solves some game story mysteries such as the whereabouts of Trema, the first leader of the New Yevon faction. Trema can be found on the 101st floor of the dungeon. Optional
Cave Dungeons
editOmega Ruins - Omega Dungeon
editCan be explored only on Final Fantasy X. The dungeon is located in an unexplored part of Spira, at the Easternmost part of Spira's large continent. It has several game goodies. Optional
Calm Lands Gorge - Cave of the Stolen Fayth
editCan be explored on both games. The dungeon is located in the northern part of the Calm Lands. It has several game goodies. Optional on FFX, mandatory on FFX2 plus the power up for Paine's special dressphere
Mushroom Rock - Den of Woe
editCan be explored only on Final Fantasy X-2. Several game goodies. Optional.
Mi'hen - Hover Crash site Dungeon
editCan be explored only on Final Fantasy X-2. The dungeon is located at the base of the Highroad bridges, where a hover crashes in chapter 3. It has several game goodies. Optional
Besaid - Wakka's Cave
editThe cave where Wakka goes on to look for his parent's sphere on Final Fantasy X-2. No goodies, Mandatory
Underwater Dungeons
editBevelle - Underwater dungeon - Via Purifico
editCan be explored only on Final Fantasy X. It is a large underground sewer full of fiends. Tidus and the rest of the guardians are thrown there by Kinoc and Seymour. No game goodies. Mandatory
Gagazet Summit - Small Underwater/cave dungeon
editCan be explored only on Final Fantasy X. No game goodies. Mandatory
Stone Temple Dungeons
editAmazing Chocobo Dungeon
editCan be explored only on Final Fantasy X-2. The dungeon is located at the back of Clasko's Chocobo Ranch in the Calm Lands. It has several game goodies. Optional
Thunder Plains - Tower Dungeon
editCan be explored only on Final Fantasy X-2. The dungeon is located at the base of the 9th calibration tower, across the lake. It has several game goodies. Optional
Thunder Plains - Dragon Dungeon
editCan be explored only on Final Fantasy X-2. The dungeon is located at the Southwest end of the plains. No game goodies. Mandatory
Bikanel Desert - Cactuar Dungeon
editCan be explored only on Final Fantasy X-2. The dungeon is located in a cave on the back area of the Cactuar Nation. No game goodies. Optional
Zanarkand - Zanarkand Dungeon
editCan be explored only on Final Fantasy X-2. No game goodies. Mandatory
Floating Ruins - Small dungeon
editCan be explored only on Final Fantasy X-2. Some game goodies. Mandatory