Which Pokémon games were the first main-series titles to feature a fully open world?

Pokémon Scarlet and Violet were the first main-series Pokémon games to feature a fully open world.

Released for Nintendo Switch in November 2022, the games take place in the Paldea region. Their world combines cities, wilderness, roads, and other locations without the traditional route-by-route structure separating major areas.

Players can pursue three main story paths in an order of their choosing. Koraidon or Miraidon serves as a mount, gaining abilities that help the player cross land, water, and air as the adventure progresses.

Pokémon Legends: Arceus is also known for broad explorable areas, but it is structured as a set of distinct open zones rather than one continuous open world. Sword and Shield introduced the Wild Area, yet most of those games still used more traditional connected routes and towns.