How dow I get to route 224?

Beat Cynthia the Pok�mon League Champion, and then that guy blocking your way in Victory Road will be gone, and you need to help this girl through the tunnel. She has an Arcanine with her.

First, you need the National Dex. Then, fly to the Pokemon League, like, the actual Pokemon League, and go in the Victory Road Entrance. Once there go south, and then when you can, go west until you pass an old man. Immediately past him are stairs, so go up those stairs, and go east until you run into a cave. Use defog there, and help the girl get to the other end. When there, go in the cave by going in that door you see, and at the end is the exit, where you'll be on route 224.

I think you need to have beaten the E4 to access that area. Anyways, fly to the Pokemon League. Surf down the waterfall, land and go into Victory Road. Go down and cross the bridge, and use Rock Climb. Go up to where the Old Man is, and then go up the slope. Cross the bridge, go under the other bridge and there should be a cave opening. Next, a room and another cave opening. Afterwards, a room with fog. Use Defog if you have it. If you haven't been there, you'll need to escort a girl through here. Fight through the trainers and use Strength and Rock Smash when needed. If you didn't notice already, it's a mini-maze. After completing the maze and finishing at the end, the girl should leave you and there should be another cave opening. Enter it, to find a large slope of stairs with a cave opening waiting for you. Enter, enter, you know. You should eventually emerge into Route 224, with trainers, berries, grass, flowers, trees etc. And a White Rock, one of the keys to getting Shaymin.