Lavaridge Town.
The first 4 gyms are Rustboro City Gym leader Roxanne, Dewford Town Gym leader Brawly, Maulville City Gym leader Watson and Lavaridge Town Gym Leader.
go to youre dads gym
go back to your fathers gym and defeat him
it is in lavaridge town
Celadon city.
You have to beat all gym leaders and the Elite 4 and Champion.
you can find one to the the left of the 4 gym leaders town.
you have to unlock celestic town
Gym Four is in Celadon City. Go right from Lavender town. Erika is the Gym Leader, and she trains Grass Pokemon.
Pokemon ruby where is the 6 gym
beat the 4 gym beat the 4 gym
You can find Rayquaza at Sky Pillar, which is west of Pacifidlog Town. You have to beat the Elite 4 before you can battle Rayquaza.