>>27401210see how there is that road that comes from the back of the island? imo you will have to go up the wooded mountain and then around to the city. otherwise the city is literally five feet from your front door.
usually in pokemon games you have to go through some grassy routes before you get to the next town. if they had a roadblock right at the curve in the road it would prevent you from getting to the town right away but then later it would allow you to return home quickly.