While Route 105 is the fifth route in Hoenn's numbering order, it is not the fifth route encountered by trainers. The only way for a trainer to cross it early in the game, in fact, is by boat. After the player defeats Norman in Petalburg City and gains the ability to use Surf outside of battle, Route 105 is able to be more fully explored, bringing trainers in contact with one of the three legendary golems, Regice, in the Island Cave.
The route essentially consists of a Surf straight south from Route 104, though a small path across a sandy island leads north to the Island Cave, where Regice sleeps. There are a few trainers, Swimmers, on this route, and plenty of Water Pokémon.
Trainers with a PokéNav by their names will be registered in the Trainer's Eyes or Match Call function after the first battle, and may have a rematch with the player with higher-level Pokémon.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.