Hollow Bastion / Radiant Garden

The Town
Sora first arrives in the Radiant Garden (still known as Hollow Bastion at the time) at the Marketplace where all the shops are located. Down the stairs past the item shop is the Borough, which seems to be a residential area and where Merlin's House is located. It's also the Hollow Bastion Restoration Committee's base of operations and leads to the world 100 Acre Wood.
If you continue, you will come across the Bailey which at first allows a look of the Villain's Vale and access to the Restoration Site. After the events of your first journey to Space Paranoids, the Bailey is changed, with the outer wall of the city broken down and you can walk to the Castle Gate.
If you go to the Restoration Site, you will find equipment to restore the city. It is also changed after your first visit to Space Paranoids, which allows you to get two new treasures. At the end of the Restoration Site you will find the Postern. The Postern leads to the Corridors under the castle which lead to Ansem's study. Ansem's study includes of his desk and personal library and his computer room. Ansem's study leads to the world Space Paranoids and the Heartless Manufactory.

Outside of the Town
If you go to the Castle Gate from the Bailey, an old gate similar to the one in Kingdom Hearts. From the Castle Gate, you will reach the long and winding Ravine Trail that eventually leads to the Crystal Fissure, a small cave-like area with glowing crystals. This leads to The Great Maw, a large area where the Battle of the 1000 Heartless is fought. The next and last area is the Dark Depths where you can fight Sephiroth after your third and final visit.

Villain's Vale
From here you have a view of the Villain's Vale which is an unreachable in Kingdom Hearts II. It acts as a base of operations for Maleficent and her forces of darkness. After learning that Maleficent was killed, Pete showed up here, to see if it was true. He found an empty fortress, but was soon greeted by a Diablo and a resurrected Maleficent. She begins to use it as a base of operations, even though now there are only two in her league.
When Sora and co. first arrive in Hollow Bastion, at the base of the Vale is a swarm of Shadow Heartless. Leon and the rest of the Hollow Bastion Restoration Committee wish to restore the city but need to get rid of the Heartless first. After the Battle of the 1000 Heartless, the base of the Vale is no longer surrounded by Heartless. The Heartless were probably amassed together by Maleficent and Pete for their army and then used to attack Hollow Bastion. The Heartless, however, sided with Organization XIII and did not finish attacking the city.
Villain's Vale appears in several flashbacks (or rather, flashforwards) seen in Timeless River. As Maleficent treats Pete badly after his failure, the latter begins wishing he could return to the old days when he captained the Steamboat Willie. In response, the worlds gave Pete a doorway to his past to atone for his mistakes. He shows the door to Maleficent, who orders him to go to the past and destroy the Cornerstone of Light so that they may take control of Disney Castle in the present.
The fortress also acts as the driving force of most of Maleficent's actions during this game. After losing Hollow Bastion to the Hollow Bastion Restoration Committee, she deems the crumbling fortress unworthy, and begins searching for a new, grander castle in which to rule, setting her sights on both Disney Castle and the Castle that Never Was.

Cavern of Remembrance
Main article: Cavern of Remembrance
In Kingdom Hearts II Final Mix, new areas are added including the Cavern of Remembrance and the Garden of Assemblage (where data of defeated Organization XIII members can be accessed and fought against). These areas can be accessed from a new hole in the Postern. Alternatively, after completing all stages in the Cavern of Remembrance, the Garden of Assemblage can be accessed via an entrance hewn out of the rock in the left side of the Restoration Site, thus saving players the trouble of scaling the mineshaft in the Cavern of Remembrance.

Although Kairi and Ansem the Wise, two characters original to the Kingdom Hearts series, called this world home at some point, this world can be looked at as the only world based on Final Fantasy in the series as most Final Fantasy characters in the game are originally from here. Scrooge McDuck, Huey, Dewey, and Louie are from Disney Castle originally.
Prior to Kingdom Hearts Birth by Sleep this was the only world to have a change of name. This trait is now shared with the Land of Departure, as well as Timeless River, though the actual name of the world in question is unknown.
Eight members of Organization XIII come from this world. Additionally, Sora lost his heart here as well, creating his and Kairi's Nobodies.
Leon, Yuffie, Aerith, Cloud, Tifa, and Cid were never shown in Kingdom Hearts Birth by Sleep, even though they are from the Radiant Garden. It was revealed by Nomura that they were originally slated to make an appearance, but scrapped them out at the last minute since he thought the story would get too confusing.



The Fountains

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The Shop

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