How do you get from mauville city to petalburg on Pokemon emerald?

Answer 1

There are two possible routes. The easier one would be to head south from Mauville and Surf over to Route 103, where you eventually encounter Oldale Town. Continue west to Petalburg.If you do not have Surf yet, you must either head through Verdanturf Tunnel (West of Mauville), continue to Rustboro, then head South and through the forest to Petalburg,

or take the whole back mountains around up to Lavaridge Town (Need Rock Smash), then past the desert to Fallarbor Town, then all the way back through the mountain to Rustboro and follow the steps above.

The method depends on which stage of the game you're in.