This leads east from Pewter City to Mt.Moon. Get a Spearow if you want. But it is very crucial for a collector to pick up a Jigglypuff, since this is the only place you'll see it. There are also many trainers along the way for money and experience. I suggest you to train the Pikachu and your original Pokémon strongly. You will meet two new kinds of trainers: Youngster and Lass. The former likes Pokémon such as Rattatas, the latter likes "cute" Pokémon like Clefairies and Jigglypuffs.
