The Four Blues—@East Blue, @The West Blue, @North Blue, and @The South Blue—are the four primary oceans of the One Piece world. Separated by the massive landmass of the Red Line and the unpredictable currents of the Grand Line, these seas form the starting points for countless adventures. Each Blue has its own unique geography, culture, and significance, playing a crucial role in the world’s history and its inhabitants' lives.
The Four Blues represent the world’s foundation, serving as the starting point for many of its greatest adventurers. Each Blue has its own challenges and opportunities, shaping the characters who hail from them. While the Grand Line and Red Line are the stage for the world’s greatest battles and mysteries, the Four Blues remain the heart of its culture and history, embodying the dreams and struggles of everyday people and the legends they inspire.