Going north-south along CA: “Pacific Coast Highway”, it is slapped up against the Pacific Ocean for most of its route. This is the slowest and by far most scenic of the five. I know of no one who has ever done the entire length of this twisty route on one trip.
You can do the stretch from the San Francisco Peninsula through Monterey and Big Sur and on to the merging with 101 near Lompoc. This is the most beautifully scenic section. But even this one section wore on my patience with its multitude of slow curvy sections, on and on for over a hundred miles. And while one is treated to one breathtaking view after another, even breathtaking views get old after hours of traveling.
Southbound, Highway 1 loses its beauty and coastal views as it enters the urban blight of Malibu.