the answer will depend on which game you have.
Defeat every other gym. The Viridian City gym is actually your last gym, not your first.
Go to viridian city and go to that gym Go to viridian city and go to that gym
The 16th gym is the Viridian City Gym.
He is in Viridian City. But you have to have beaten all the gym leaders to have him in Viridian City. Good Luck!!
Viridian City.
Viridian city.
He won't be in viridian at first he will be at cinnibar island if you talk to him he will go to the gym in viridian city go to viridian city to battle him.
Viridian City.
Blue, the Viridian gym leader(looks like your rival for Pokemon FireRed/LeafGreen), is on Cinnabar Island. Talk to him and he'll say a few things, then go to his gym in Viridian City.
Viridian gym i forgot his name the team rocket boss guy.
The last gym is found in Viridian City
Viridian City.