You can't get past route 18 because there's nothing past it.
Close to home. Use Surf at route 1, go to the island and head west. You'll find route 17 and 18 past the gate.
yes on route 18
On route 18
on route 18
by Nuvema Town
route 18
Route 18
Route 18.
Route 18
On Route 13 by someone or Route 18.
you get it in route 18
Larvesta