The Sevii Islands sideplot actually begins as soon as the player has defeated the Cinnabar Gym and obtained the Volcano Badge. The Sevii Islands follow a trend set by Pokémon Gold and Silver, and provide most of the post-Pokémon League plot in Pokémon FireRed and LeafGreen. The Sevii Islands as seen in Pokémon FireRed and LeafGreen The seven major islands each have a settlement, which are named numerically.
These islands cannot be surfed to to travel from island to island a Pokémon Trainer must take the Seagallop Ferries from another island or Vermilion City in Kanto. The nine Sevii Islands are a part of the Kanto region, located to the south of mainland Kanto. The population of Sevii Islands is 212, including all towns and other areas.