The original Pokémon games take place in the Kanto region.
Kanto is the setting for Pokémon Red, Green, Blue, and Yellow. Players begin in Pallet Town, travel through cities such as Pewter, Cerulean, and Saffron, and ultimately challenge the Pokémon League on the Indigo Plateau.
The region contains eight Gym Leaders, each associated with a city and a specialty. Defeating them earns the badges needed to qualify for the Pokémon League. Team Rocket also operates throughout Kanto, creating the main criminal threat in the original story.
Kanto is based on the real Kantō region of Japan, although the game presents it as a fictionalized landscape. Later games revisited Kanto in Pokémon Gold, Silver, and Crystal, and the region also inspired remakes including Pokémon FireRed and LeafGreen. Because Kanto returned so often, it is sometimes mistakenly treated as synonymous with the entire Pokémon world.