Where is the island of lost Pokemon in Pokemon Pearl?

In Pokémon Pearl, the island referred to as the "Island of Lost Pokémon" is actually a part of the game's lore rather than a physical location you can visit. It is associated with the Pokémon known as Manaphy, which can be obtained through special events or by transferring from Pokémon Ranger. In the game, players can explore various areas, but there isn't a specific island dedicated to lost Pokémon. Instead, players often discuss it in the context of the Pokémon's mysterious background and the mythology surrounding it.