If at all possible, don't try to follow 101 thru San Francisco. If you really need to drive across the Golden Gate Bridge, park the TT someplace first.
When you get to LA, you might consider one of the interstates to minimize traffic congestion woes, but you can also just time your trip and avoid rush hours.
From Seattle, stay on 101 and go up and around the Olympic Penninsula. Visit the rain forests on the west side of the National Park. Drive or ride horses on the beach at Ocean Shores.
Just into Oregon, spend some time in the Astoria area - Lewis & Clark country and lots more. Stop at the Tillamook Dairy for cheese and ice cream. South of Tillamook, detour out to the Pacific City area and enjoy the beach and some quirky places to eat.
Lincoln City is always fun if you like antique shops. Newport is well worth some time . . tour the lighthouses. Stop in Depot Bay for whale watching. See the animals at Sea Lion Caves north of Florence. From Florence to Coos Bay, rent an ATV and ride the dunes. (There's a popular surfing spot at Winchester Bay.)
South of Coos Bay, don't pass up Shore Acres State Park and Cape Arago State park. Great views and good views of an elephant seal breeding beach.
Into California, the redwoods are always worth a few days. You might consider a detour south of the redwoods and head out to the ocean and pick up CA-1 for a while. Some while-knuckle driving, but the scenery is spectacular.
Inland from 101, the Napa valley is very tasty. We tend to avoid the San Francisco area, but just south on 101 is San Jose. The Winchester Mystery House is a must. Then head to the coast again for Monterey and Carmel.
Don't miss Hearst Castle and the Pismo Beach area.
Plan on spending time in the Santa Barbara Area. It's a delightful town.
And of course San Diego has bunches of stuff in Balboa Park - you could spend a week in just that one park.
And that's just for starters. Have a bunch of fun. We've been wandering up and down 101 for several years now, and always find a few surprises on every trip.
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