Johto is the fictional region where Pokémon Gold, Silver, and Crystal are set.
The second-generation games introduced Johto as a new area connected to Kanto, the setting of Pokémon Red, Green, Blue, and Yellow. After completing the Johto portion of the adventure, players can travel to Kanto and challenge its Gym Leaders, making the games unusually expansive for their time.
Johto is inspired by the Kansai region of Japan, while Kanto is based on Japan’s real Kanto region. Their close geographic relationship in the games mirrors the regions’ real-world proximity. Cities such as New Bark Town, Goldenrod City, and Ecruteak City give Johto its distinct identity.
Gold and Silver also added 100 new Pokémon, bringing the Pokédex total from 151 to 251. They introduced features including a day-and-night cycle, Pokémon breeding, held items, and the Steel and Dark types. Crystal later added animated Pokémon sprites and a female playable character option.