Kanto is the region where Pokémon Red and Green are primarily set.
Players begin in Pallet Town and travel through Kanto while collecting badges, training Pokémon, and progressing toward the Pokémon League. The region contains eight Gym Leaders, the Elite Four, and the Champion challenge.
Kanto's locations include Viridian City, Pewter City, Cerulean City, Celadon City, Fuchsia City, and Saffron City. Its geography includes forests, caves, oceans, routes, and the volcanic Cinnabar Island.
Kanto is also the setting most closely associated with the original 151 Pokémon. The region returned in later games, including Pokémon Gold and Silver's post-game, and was re-created in Pokémon FireRed and LeafGreen. Johto, Hoenn, and Sinnoh are separate regions introduced in later generations.