We started our trip up the coast in Sonoma County. We rented bicycles in Healdsburg and spent the day biking from winery to winery. The trick about this is that there are so many wineries that it quickly becomes overwhelming and you have to start ignoring many of them and stopping at every third or fourth one. Some intersections in the Dry Creek Valley actually have as many as 30 directional signs to different wineries. Dry Creek specializes in Zinfandel so by mid-afternoon we were overdosed on Zinfandel tastings and returned the bikes in order to drive north to the Alexander Valley where we could overdose on other wines. Armed with rather a lot of wine purchases (and assorted other wine products like mustards and vinegars) we headed north to Ukiah. If you're in the area, Mendocino brewing has a very oddly located brewpub in the town of Hopland. Ukiah Brewing is a nice place to eat as well.
The beer and wine continued the next day as we headed for the coast. Besides the big wine regions of California, there are literally hundreds of smaller lesser-known areas. This is the Navarro River valley. Outside Sonoma and Napa, prices become much more reasonable for bottle and case purchases. Not far from here in Booneville, CA is Anderson Valley Brewing which is a must-stop for beer lovers. They have a nice little tasting bar, a small herd of ponies, a disc golf course, and a dog who wants your pretzels.
Also in the area is the Navarro River redwood grove. Most people focus on either Humboldt River or Redwood National Park but there are many other redwood state parks surrounding these areas and realistically - they are just trees. They're much the same regardless of which park you're technically in while visiting them. The road from Boonville to Fort Bragg can compete scenery-wise with any road in the world.
The coast along highway 1 either direction from Fort Bragg is quite scenic with a multitude of state parks (mostly at river mouths) and also some impressive headlands projecting out above the ocean.
Continuing north, highway 101 cuts inland and goes through Humboldt Redwoods State Park which is just as popular as the national park (moreso when we visited). Humboldt features one of three 'drive-thru' redwoods all of which are privately owned tourist traps, yet they seem to draw people nonetheless. There is a lot of good hiking through Humboldt, especially off the one east-west road coming in from Honeydew.
Redwood parks continue on up the coast towards Oregon. We based ourselves in the Eureka-Arcata area while visiting. Eureka is a suprisingly nice town that you'll be forced to drive through the middle of anyway so you might as well stop awhile. Arcata is just across the bay and doesn't have quite the downtown scene that Eureka does, but it has a whole lot of hotels.
Half an hour's drive north of Arcata the Redwood National Park component begins at the town of Orick, which is really just an intersection. This a random beach just south of the park's visitor center. From all accounts this would be a relatively non-foggy day in the area. We saw the sun quite a lot in the afternoon.
Supposedly the centerpiece of all these redwoods is the Lady Bird Johnson Grove which is where the national park was dedicated. It's really just a way to concentrate most of the hikers in one small area, since there's nothing here that isn't found in the rest of the redwood areas. There really aren't very many trails running through the national park and most of them are short loops like this one.
North of Orick, the park includes the California coast and a particularly impressive stretch just south of the mouth of the Klamath River. There are thousands of sea birds here, and there would be a decent view of gray whales if any happened to be passing by. If they were, we didn't notice them.
Our favorite of all the redwood areas would have to be Jedediah Smith State Park way up near the top of the state. The one annyoing thing about all these park components is that the rangers are very provincial and territorial about it all. Don't even consider asking a National Park ranger about a State Park trail or vice versa even if it's just a mile or so away. When we asked at the Jed Smith visitor center about the road through Smith River Recreation Area (bordering the visitor center!) we were told that "isn't part of my park". Either way you don't need rangers to enjoy the hiking around the park. Best bet is anything off of Walker Road. Just park somewhere and start wandering. You can attempt to use a trail map but there are probably twice as many actual trails as are marked on the map and the narrow corridor of the park makes it fairly hard to get lost.