The third gym leader is in Hearthome City. But i think the gym leader says that you are not ready yet. (don't remember) you have to beat Pastoria and Veilstone's Gym leader first and then you can battle Hearthome's leader.
Snowpoint city at the top of shinno Pokemon daimond & Pearl
In the goldenrod gym.
The third gym leader in Pokemon Sapphire is Wattson and he is located in Mauville City.
The third gym leader in poekmon pearl is maylene, a fighting type gym leader.
'farfetch'd does not evolve' what? the third gym is in mauville. The leader is 'wattson' and he uses electric pokemon.
marshtomp
26
go to the Pokemon gym
The third gym leader is in Goldenrod City in the radiotower. after you get the radio card she goes to her gym to the east of the radiotower.
Veilstone city,the gym leader is a fighting type
I have Pokemon platinum the 3rd gym leader always their your probaly just not lucky.
its easy think it