Pokémon FireRed and LeafGreen/Viridian Forest

'The nature preserve is smack-dab in the middle of Route #2, the route that runs between Viridian City and Pewter City. Pokémon are plentiful within its borders, and many trainers come here to capture new specimens for their collections or to challenge other trainers. It's easy to lose yourself in Viridian Forest if you don't know where you're going.'

Through the woods
As you try to cross Viridian Forest, you'll be attacked by both wild Pokémon and various trainers who come at you when you cross their line of vision.

Their pets and the wildlife here may seem tough, but much of it isn't since Kakunas and Metapods can't attack! Don't bother trying to capture them... Instead, capture Weedles and Caterpies and let them evolve into Kakunas and Metapods so they can keep their offensive abilities. They evolve fast: Both will be at their third stage of evolution by Level 10!

Pikachus are extremely rare, but don't leave without snagging one. Defeating Misty will be difficult without their help!