Turnback Cave

Turnback Cave (Japanese: もどりのどうくつ Returning Cave) is a maze-like cave filled with dense fog which is home to the Legendary Pokémon. Turnback Cave is located at the north-central region of Sendoff Spring, which itself may only be accessed through the Spring Path.

In, there is an inscription in the pillar in the room Giratina resides in that implies the cave is a location where the separation between the real world and the Distortion World is weaker. In, a portal to the Distortion World appears in front of the pillar. The inscription reads:
 * This is... That where life sparkles... That where life has faded... A place where two worlds overlap...

Rooms and pillars
When a player exits a room, the next will be randomly chosen from a selection of possible rooms. If the player walks out the door through which they entered a room, they will return to the entrance room; from the entrance room, the player can exit to Sendoff Spring. If the player navigates 30 rooms without finding the third pillar, the next door returns them to the entrance room. Escape Ropes and cannot be used to escape. The inscription in the pillar at the entrance room reads:
 * ...Past three pillars...to the sleeping... ...before 30 is surpassed...

After the player has found three pillar rooms, the next room will be Giratina's room. In Pokémon Platinum, Giratina will only be in this room if the player did not catch it in the Distortion World. If Giratina is not present, there will be an item each time it is reached, with the item depending on the number of rooms the player navigated to reach it: a Reaper Cloth if they reach it in 3 rooms, a Rare Bone if they reach it in 4 to 15, and a Stardust if they reach it in 16 to 30. In, after catching Giratina, there will also be a portal to the Distortion World, where the player can obtain the Griseous Orb.

When the player reaches a pillar and examines it two numbers will appear: the top number indicates which pillar the player is looking at, and the bottom indicates how many rooms the player passed through on the way to it.

Items
Before being able to obtain the item at the end of the cave, the player must first catch or defeat Giratina. In, if the player defeated Giratina in the Distortion World, they must defeat or catch it here and traverse through the cave again in order to be able to obtain items here.

In the Pokémon Adventures manga
In the, and Volkner entered the Distortion World through the cave. They were later followed by, , Cheryl, Riley, Mira, Marley, and the Advanced level Grunt. After leading the group to the portal, the Grunt was about to head out, but he was stopped by Platinum, who voiced her distrust towards him. She, however, promised to protect him from Team Galactic, to which the Grunt agreed and led them through the portal.

Trivia

 * Turnback Cave is similar to locations in Kanto and Hoenn.
 * In Kanto, Cerulean Cave can only be visited after defeating the Elite Four (Generation I) or obtaining the National Pokédex (Generations III and IV), and is home to high-level wild Pokémon and a.
 * In Hoenn, the Sky Pillar is home to high level Pokémon and a, and in the third version it can be visited before entering the Hall of Fame.
 * Turnback Cave's system of seemingly random room layout may be an advanced version of the system used in Lost Cave in the Sevii Islands in.
 * Turnback Cave and the Distortion World may draw some inspiration from the Japanese underworld, . Giratina itself can be seen as a parallel to the kami.