To be able to use Flash, you need to have the HM for it. In this case, Cut is needed. If you don’t have Cut yet, go to the grassy area on Route 24 (the one with a house in the middle) and talk to the man there. He will give you the HM01 Cut.
Once you have Cut, return to Celadon City where you originally received the bike from the Game Corner owner. Go straight north from there and jump over the ledge into Lavender Town. Now go west until you reach Route 10, then enter Saffron City through its northern entrance.
From here, head south along Route 8 until you reach Celadon City again, but this time enter through its southern entrance on Route 7. From here, simply head northwest until you reach Fuchsia City and then go east along Route 19 until it becomes Route 20 (you’ll see a sign saying “Saffron Gate”).
Now go northeast until you reach Vermillion City and then head west along Route 12 until it turns into Route 13 (you’ll see another sign saying “Vermillion Gate”). Continue going west along this route until.
Last modified: August 2, 2022