@RobertDevv you must remember, in their world, they thought they where the only ones in the continent, what does that mean? Long travel via water was never something they had deemed necessary, they never knew there is another or maybe more continents, same thing with planes and even cars, why? Their world reliea heavily on magic, so making things like steam engines wasn't something they needed, why make steam engines when you can just hire a mage to do said job? At around the early stages of Artgurs arrival to his family after getting separated (4-6 year old Arthur) he mentioned that this place wasn't very advance since everyone relies on magic, what i could say is that Arthur (king Grey) is from a futuristic world where they have explored the whole world, so I don't understand how he doesn't remember the possibility of other continents existing. As for why they thought they where the only ones to have boats, well they have NO information about the other continent, and since their discovery of boats was just recent, they also thought the other continent might not had discovered the boat too, for all they know, the other continent could even have planes and other stuff. Holy yap