Pokémon Ruby and Sapphire/Route 105

Now that you know Surf, you'll get an opportunity to capture Pokémon, gather items and battle trainers.

Trainers

 * Swimmer Dawn


 * Swimmer Beverly

On the western edge of this waterway, you'll encounter a long vertical island. Search it to find a trainer.


 * Ruin Maniac Foster

Once you beat Foster, Surf on the west side of this island. Beat this trainer:


 * Swimmer Austin

Surf up to the rock formation to the north, this one will turn into a cave (Island Cave) when you decipher the message in the Sealed Chamber. Make sure to return here. For now, continue south. At the southern tip of the island is a trainer.


 * Swimmer Luis

Surf south, sticking to the western rocks. Search the islands to find an Iron. Then continue south to Route 106.