This route has a stream running next to it, so maybe you'll find some water type Pokemon. Also, Route 5 to the Lost Tower branches off from it.

Pokemon:
On land:
Ponyta
Buizel
Ryhorn
Geodude
Nidoran(male)
Nidoran(female)

Water:
Magikarp
Buizel
Feebas
Goldeen
Basculin

Fishing:
Magikarp
Feebas:
Goldeen
Basculin
Gyrados
Barboach