Sugar Island

Introduction
Sugar Island is situated in the first half of the Grand Line. It is one of the first islands past Reverse Mountain.

Rum Runners' Paradise
Years before the One Piece storyline began, Sugar Island was used as a hideout for rum runners. The island's various caves were the perfect hiding spots for the runners to make their own rum and then deliver it to islands all over the Grand Line. They would undercut merchants in order to sell more of their product and make a huge profit. This angered the merchants and many of them banded together to put a stop to the rum runners. The merchants contracted a small army of bounty hunters to eliminate their unwanted competition.

The bounty hunters assaulted Sugar Island and began clearing the island of the rum runners. It took three days, but the bounty hunters finally went through all of the caves wiped out the last of the rum runners. They returned to the merchants and claimed their pay. Eventually, the island was forgotten and left uninhabited. It was no more than a stop for pirates trying to navigate their way through the Grand Line.

Geography
Sugar Island is a Spring Island. It is mostly temperate rainforest, except for the caves below. The island has dozens of caves that connect and form a labyrinth beneath the island. There are multiple treasures that remain hidden in the caves from the time when the rum runners called it home. However, pirates that go looking for these treasures often end up getting lost in the numerous caves and die trying to find their way out. So far, none of the island's treasures have been claimed.

Trivia

 * The story of Sugar Island is inspired by the rum runners of the real world during the Age of Pirates.