Northern California road trip - itinerary advice

Since you've got wheels, consider Santa Rosa -- the presence of the casino means that there are lots of larger-sized hotel rooms available at reasonable rates, and travel times to natural wonders and wineries are pretty reasonable.

If you have time I'd suggest getting out to the coast as soon as you can north of SF. Point Reyes is well worthwhile, then just keep going up 1. I spent a night in early May at the Best Western in Fort Bragg and it was fine, but maybe too late to book now. There are lots of resort-type places and B&Bs along the way. Highlights for me were Fort Ross and McKerricher Beach (just north of Fort Bragg).

The road from 1 to 101, north of Fort Bragg, is scenic but slow with lots of twists and turns as it goes inland. You might do better to just turn around and let the people on the passenger side see more of the ocean.

If your trip is long enough, you should know that 101 between Klamath and Crescent City has a major construction project with multi-hour delays as traffic is routed onto a single slow lane. Once you're up there you have no real alternative if you want to continue toward Oregon.

Petaluma, Jenner, Geyserville, Healdsburg…. All good places to stay.

You could also investigate a Sea Ranch rental near Gualala.

I am sure you can visit Pt. Reyes from Petaluma. We have many times gone to Pt. Reyes from Berkeley for a day, a long drive, but quite doable, so it should be easier from Petaluma. Also, have you looked into what might be available in Marin county away from the coast? There are lots of motels along Highway 101.
I would recommend against any lengthy driving on Rte. 1. It is really challenging, narrow, with lots of hairpin turns, and lots of ups and downs.
As far as places other than Pt. Reyes, Muir Woods is beautiful. Check about whether reservations are needed.

I don't mean to be a downer but watch out for fire season - it's a real possibility with the ongoing drought conditions (I used to live in CA for 20+ years and it has gotten more frequent in recent years).

I would try to go to Lassen Volcanic Park given its incredibly short tourism season. Ukaiah is a neat place to stay near Mendocino National Forest. I'm sure that there are some places left inland to stay altough it's pretty late to get decent prices.

Petaluma would be fine. Coast is accessible. Muir Woods, book in advance if you are interested. You can enjoy time in Sausalito on the way to Petaluma. Haven’t been to Mendocino or that far North for awhile. Humboldt county maybe interesting too. It was known for pot growing, and with pot being legal, some of the sleepy little towns maybe worth visiting. Not to buy pot, hahaha, but there maybe off the beaten path things to do. Bodega bay is fun to check out. Hitchcock filmed the Birds there. It’s an active fishing port too. Wine country in Sonoma is fun and we prefer Sonoma to Napa.

Prioritize what you like to do, check out google for ideas to fit your priorities.

As another poster said, keep an eye on fires. Sonoma county has had major fires it seems each of the last 3 summers.

It really depends on what you want to see. If you want to do beach type seashore you're pretty much limited to the area south of Ft Bragg. If you want rocky coastal areas that's best above Eureka. If you want wine country you have a lot of choices; Napa Valley, Santa Rosa/Healdsburg, Medocino, and the Alexander Valley (often overlooked). If you want redwoods you have the coastal forests like Jedidiah Smith or the inland groves of Humboldt.

Everything on this list is within a couple hours drive from Napa. I lived there for 7-8 years and going across the backroads to Ft Bragg or Eureka was a normal Sunday drive. I'd suggest figuring out what you want to see and then looking for where to stay. Sea Ranch is very nice, but probably booked. Gyeserville/Healdsburg/Calistoga is pretty much central to Wine Country. Eureka is good if you're doing the northern redwoods. Redding if you want to catch up on some mountain hiking and fishing. Bodega Bay is nice too, certainly better than Petaluma if you're doing the coast.

If you want a road less traveled, take Skaggs Springs Road out of Geyserville past the dam and over to the coast. It's an old logging road that cuts across the top of the coastal range and is fantastic on a sunny day in a sports car with the top down. Very much locals only...

I almost forgot, the kids may like a whitewater run on the Russian River. They have a lot of those tours.

A big word of thanks to Dick for your above mention of the roadworks south of Crescent City. I had planned my original itinerary to travel that route today, a Monday. After reading this thread, I checked the road works schedule and modified my itinerary to travel through there 1 day earlier, on Sunday. So instead of possibly hitting the 4 hour weekday closures, I had two 6 minutes delays where traffic was routed through a single lane. Boy did I feel like a smart traveler.... thank you!!

And for anyone considering trips in this area now (August 2021) please note that certain smaller towns (like Mendocino) have severe water shortages.