A continent on the planet Rigel Prima where many focused events of the RP take place, noted for having a high concentration of dimensional rifts that appear and disappear in its boundaries. Because of this activity, Belle'Ayn isn't as densely populated along its west half where rift activity seems to be worse.
Belle'Ayn serves as the continent where most of the RP's focus happens. Most player's main characters call Belle'Ayn home and thus most of the canon's events, arcs, and slice of life moments occur there.
The name of the continent is a restructuring of 'BLN', Better Layton Never's acronym.
There had been other countries that existed within the Great Plains and Northern Wilds that no longer are around. These lost civilizations have something to do with Equestria and the First Contact War.
Belle'Ayn has no jungles or tundra climates, as well as few wetlands.