Los Angeles to Monterey, CA

I-5 through the Angeles Mountains has some pretty ferocious grades, especially the infamous Grapevine at the north end of the mountains. North of that, I-5 has to be one of the most BORING stretches of road I've ever been on (it's right up there with I-10 in New Mexico). Also, the last time I drove I-5 (roughly 15 years ago), the stretch north of the mountains was rather rough.

Even though you are coming back that way, I still recommend the 101. It doesn't take all that much longer, is way more pleasant to drive, and you avoid those killer grades.