Sendoff Spring (Japanese: 送りの泉Sendoff Spring) is an area east of Route 214, accessible via the Spring Path. It is known as the "fourth lake of Sinnoh that was kept secret", and is said by some to be where the deceased go to journey to the world beyond. On the shore of the lake in the center of the area is the entrance to Turnback Cave, where the barrier between the Pokémon world and the Distortion World is weaker.
In Pokémon Diamond and Pearl, the spring cannot be visited until the player has entered the Hall of Fame. However, in Platinum, the player arrives here after escaping the Distortion World the first time, after catching or defeating Giratina. However, the player cannot enter Turnback Cave until later as Cynthia is blocking the entrance. Once the player has entered the Hall of Fame, the entrance will be open to enter the Turnback Cave and obtain the Griseous Orb.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
Despite being known as Sinnoh's fourth lake, the Town Map does not display the lake ontop of the yellow area indicating the route, instead being displayed underneath it.
This can be explained as the lake has been 'kept secret', and thus would not appear on any map.