u go to the right of the city fortree then through the grass then get on the bridge and keep giong to u see proffesor.
fortree
go to the next citi
in the fortree city
go to fortree city and battle winona
the 6th gym leader is in fortree city after the weather station where you get castform
You go to Fortree City to take on on the flying type gym leader!
Go beat the 6th gym leader ^^, that is in Fortree City.
go to your dads gym at Petalburg city and beat him to get surf from you friends dad than you surf around places or go to fortree city.
The Fortree gym.
Fortree City.in fortree city
The sixth gem is with Leader Winona in Fortree city. You need surf to get to that city. You get surf from Wally's dad after you beat the fifth gym. You surf there from Mauville.
Hmm...you just beat the Sixth gym located at Fortree City(maybe I write wrong).That gym was flying type.Hope this help u^^