Even if you never looked at the street signs, you still couldn't get lost: the pavement itself frequently bears markings like this, both confirming that you're on the route and indicating the direction in which you should be traveling. The lower sign says "Ononmichi" in the direction of the arrow; the upper sign points to Imabari (the Shikoku city nearest the last bridge).

The former backwaters are very cognizant of the fact that they are now on a major travel route, and they have not been slow to take advantage of the fact by attempting to revitalize their economies. The Innoshima Flower Center is one attempt; there are promotions for it everywhere you look. While I declined to tour the garden itself, I did invite the pretty receptionist to model for my photo, and was rather surprised when she accepted the invitation.