Byrne Island is a large island located in the Diamond Archipelago. There are three known routes from the island: Alpha Island, Papaya Island, and an inter-archipelago route to Remora Island in the Sapphire Archipelago. There is also an extinct training route encircling the island. Byrne is home to Sheepish Jimmy, a sheep, and In Memory of Jerze, a cat placed in memoriam of the pirate Jerze.