You get your 3rd badge in Veilstone city against Maylene.
the fourth gym is in celadon city at the bottom left of the city. the gym leader is erika. the badge is called the rainbow badge
Veilstone city,the gym leader is a fighting type
viridian city
The third gym leader is Fantina, and she is in Hearthome city. The only way to get there is from oreburgh going through mt. coronet. Hope it helped.
1. Coal Badge-Roark, Orenburgh City 2. Forest Badge-Gardenia, Eterna City 3. Cobble Badge-Maylene, Veilstone City 4. Fen Badge- Crasher Wake, Pastoria City 5. Relic Badge- Fantina, Hearthome City 6. Mine Badge- Byron, Canalave City 7. Icicle Badge- Candice, Snowpoint City 8. Beacon Badge- Volkner, Sunyshore City If you need to know what levels his Pokemon are just ask me :)
Veilstone City
You should go to Canalave city
in eterna city
the third badge in sapphire is at mauville city(north of slateport city)
The third badge is in Goldenrod City.
Snowpoint City.
sunyshore
vermillon city
== == You get the 8th gym badge in Sunyshore City. Hope this helps
In Vermilion city.
Go to hearthome city and beat the gym.
if you are looking for the third gym badge i suggest Veilstone city.