Battleship Island

Battleship Island Is considered the island of the base of operations for Marines stationed in the South Blue. It serves as the guard that protects the entrance of to prevent pirates from entering the. It is led by Commodore and inhabits numerous captains along with many lower ranking marine soldiers when they weren't assigned to another base or has just entered the South Blue.

Geography
The island is a massive fortress made by the Marines that was crafted into a valcano with a land mass surrounding it.