Chronicles of Murlonio
The world you live in is a vast ocean dotted with thousands of islands. People refer to the world as The Great Sea, as a staggeringly high percentage of the planet is water.
The Sea is lethal to any mariners who try to navigate it without the proper knowledge. Ancient routes, lanes known to be relatively safe, connect the islands to each other. These routes have been passed down through cartographers, explorers, traders, and fishermen since the first people began sailing.
Gargantuan monsters, sudden and severe weather, and other mysterious forces claim many ships who stray from these safe routes. A safe route that completely connects all the islands on the Great Sea does not exist. Most islands simply trade and communicate with the few islands closest to them. This practice creates many isolated groups of islands, and it limits the goods and information available to these people.