The edge of the map is where your ancestors wrote “unknown.” Somebody still had to go look.

Every mapped place was unmapped until somebody walked into it with no guarantee. The blank spaces were not blank because nothing was there, only because nobody had gone and come back to say what was. Someone always has to be first, and that person never has the map you keep wishing for.

None of this requires an ocean. Take the part of your own life nobody has explained to you and go find out directly: ask, visit, try. Then write down what you learned, so the next person gets a shorter walk than you had.