Calm Belt

The Calm Belts are the areas just north and south of the Grand Line. These areas almost never have ocean currents or winds blowing, and are also nesting grounds for Sea Kings. They are very effective barriers for those trying to enter the Grand Line.

However it was revealed that the Marines crossed the Calm Belt by using the Seastone lining at the bottom of the ship where a Sea King won't notice a ship above them.

First Appearance: Chapter 101; Episode 54