Yep, nine lighthouses in Oregon, most of them are nicely accessible, too. They are so picturesque. If I were more of a collector I'd want to have a figurine of each -- I coveted them in the gift shops.
It was a long drive for us, too, about six hours coming from the Seattle area. One of the things that we lucked out on, as well as the weather, were the wild flowers and shrubs... there were hillsides of wild strawberries in full bloom, native purple iris which were gorgeous, purple and yellow violets, rhodies, wild ginger, ferns, huckleberry bushes, blooming salal, yellow gorse.... just an amazing array of spring growth.
I've been on other scenic byways but this one was among the best because we could stop nearly anywhere and enjoy the beach. I think I read there were 40 state parks along the way, as well as all sorts of established viewpoints, national registry places, information boothes, museums and visitor centers. There were also some good restaurants and hotels.
I've also liked the drive out to the Florida Keys (I'm pretty sure that's a scenic byway, too) and Butrfly's right... the California coast is truly great, though there's a lot more traffic and it seemed less accessible, as I remember it -- the beach is further away from the road (which is good once you're on the beach!). Oregon is just standing on her head to make it easy for tourists. I love the idea of a scenic byway -- giving the drive-by tourist a chance to enjoy the view!