We've seen Zelda: Breath of the Wild "out of the map" glitches before, but not like this.
You see, past methods have generally been shoddy at best. Although they get the job done, they often bug out the game, or don't allow you to save at certain points. Gaming Reinvented says they're past that now: they're post buggy-bugs.
In the below seven-minute video, Gaming Reinvented walks you through the process. You need to head to the Gerudo Canyon Stable, then grab your horse. Turn around and ride down the ravine path roughly 45 seconds into the video. Then save, and fast travel to any apparatus shrine: accessing its storage within. Reload the save, then head to a shrine "far away from the area" (the example is a northeast location).
VoilÃ : your character will fall off the map and then part of the process is complete. From there you need to compete in an archery game, moon jump, land on a wild horse, then moon jump across the entire map.
It's anything but "easy," as the video describes, but it's allowed folks to explore the world in a new way and break the "you can't go any farther" boundaries.