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.
He's at Cinnabar Island.
In the beginning of the game, he isn't there. Towards the end, you will find his rival on cinnabar island by himself. After you talk to the rival, he leaves to go back to viridian. Fight the cinnabar gym leader, go back to viridian and the gym leader should be there. The man you talk to on Cinnabar Island Isn't the gym leader, but his rival. After you speak with his rival on cinnabar, the gym leader reappears in viridian. You have to fight and beat the cinnabar gym leader first.
They are found in Viridian Forest. However they are very rare to come by.
on thurs afternoons go to viridian forset and look for him
I know in Soul Silver your can only get him in the Viridian Forest . Pretty sure it is the same for Heart Gold
The Viridian Gym leader (Blue) is at Cinnebar Island, you can go there by surfing south from Pallet Town. If you want him to return to his Gym you have to beat the other 7 Gym leaders in Kanto
The last gym badge is in viridian city for Kanto. For Johto it is in Blackthorn city.
viridian forest in the kanto region after you beat the elite 4 for the first time you can go there
i caught a pikachu. just wait a little while and it will come.
ecruteak city
In her Gym
viridian forest