Great Barricade Reef

The Great Barricade Reef (大々的立てこもる岩礁 Gureeto Barikeedo Anshou) is a large expanse of Full Coral, and the only location known for getting it. It lays between two islands with only small sections being low enough to pass through. Though, no one truly knows how long it is, the estimate is somewhere between one to two hundred miles long and is known for being home to much of the coral-covered wreckage.

History
Though not much is known about this location, it is believed that 600 or 700 years ago an orange meteorite fell from the heavens and sunk between two islands. As time progressed, coral began to grow in a bright orange color at great pace. Ship travel between the two islands soon became a hassle as the coral never stopped growing, as explorers tried to cross, maps were made of sections that were low enough for the crews to pass and each year new maps were made as it always changed.

Though, it is unknown where he came from. The ruler of the Great Barricade Reef seems to control the coral, A Kanikani, though hardly has ever seen him. A number of infamous pirates and marines have crashed here, it is rumored that Gol D. Roger met Kanikani who allowed him permanent access through the reef. It is unknown if the Straw Hat Pirates, but judging by Luffy's luck, it is best guess they passed through without knowing it.

The most recent crash site is that of the Hitokai, a large slaver vessel which ran aground around 14 Years ago. Though it is unknown if anyone survived.

Trivia
Location Grand Line Location
 * The name is based off the fact it acts as a barrier and the famous Great Barrier Reef.