You have to beat Erika, who is the fourth Gym Leader, raises Grass-Type Pokemon, and resides in Celadon City.
canalave city gym
beat everyone in silph.co and you can get into the saffron gym
you need to beat flannery at the gym in lavaridge town
beat silph co. building then the gym will be open
beat the 8th gym which is in the next town after the town which you live in
unova
the fourth gym its a fire gym
beat a gym leader
beat the gym
the best way to beat the 7th gym leader is with a fire type Pokemon
canalave city gym
beat bryon in the steel gym, canalve city
With good Fire of Fly Pokemon!
beat everyone in silph.co and you can get into the saffron gym
use fire
Get a good fire type Pokemon
revive a pokemon from a fossil and beat the fire gym leader Actually, you need to get the key from the Pokemon Mansion. It wouldn't make sense to require you to beat the gym in order to unlock the gym!