Raijin Island

Raijin Island is one of three islands in the New World you have to visit, if you wish to proceed futher into the new world (without an eternal pose) after passing through the Red Line.

It is the island which deviated the Log Pose the most and as a result Vice Admiral Smoker expected the Straw Hats Pirates to head to this island after leaving Fishman Island.

It's also the same island that the Fallen Monk Pirates saw when they entered the New World before the timeskip.

Trivia

 * Raijin is the god of thunder in Japanese mythology.