The Oregon coast is my jam, so siddown and buckle up. Northern Cal and southern Oregon are fairly empty (by Oregon coast standards anyway) between Eureka and Coos Bay with little towns here and there, north of north of Coos Bay it starts to get a little thicker and by the time you get to Florence you are well and truly in tourist country. Everything north of Newport is basically one long strip town until you get to Astoria, with massive amounts of kite stores and bed & breakfasts and kitchy art shops everywhere.
Highlights are the redwood forests, natch, do lots of hiking there because those things are way cool. My home turf is kinda the section between Florence and Newport so that's what I know the most about. The dunes just south of Florence are a great place to rent dune buggies, which is wicked fun. Everybody will tell you eat at Moes, but f*ck that tourist trap, it's highly overrated. In Florence, I like the Bridgewater Fish House for funky seafood and the Blue Hen Cafe for comfort food. In Newport, you eat at The Chowder Bowl for awesome seafood (I order a captains platter and a big bowl of chowder, and I don't eat again until next day) and if you're still there the next day you grub at Nanas Irish Pub for killer sausage rolls and decent beers. Whale tours are fun if it's the right time of year. The beach and lighthouse at Heceta Head are favorites (actually, every lighthouse is a favorite, check out every one you have time for but Yaquina Head and Cape Mears are also not to be missed). If the tide is right, the Devils Churn is a fun waterspout. The Hobbit Trail is a cool hike. The beaches and tide rocks are Strawberry Hill are cool. The visitor center at Cape Perpetua is cool. Shell mounds are easy to find, and some of the only physical signs that the area was once populated by coastal Native American tribes everywhere. Neptune Viewpoint has one of my favorites, and is another cool beach for beachcombing and cool rocks and such. Haystack Rock at Cannon Beach has good tidepools, but there's lots of others. Plan to visit one at low-low tide if you can, they're a hoot. Newport has the Oregon Coast Aquarium, the Hatfield Marine Science Center, and the Ripley's Believe It Or Not wax museum that was really awesome when I was ten but I haven't been since so might be cool or might not? Tillamook has the Octopus Tree which is neat, and a tour of the Tillamook Creamery is a must. Everything between there and Astoria is a bit of a blur of coffee joints and wind chime shops that I've never paid much attention to, but Astoria has a ton of history - check out Fort Stevens and the wreck of the Piper Iredale for sure, but there's tons more around too. And mostly, take your time and hit every turnout and state park and wide spot in the road you feel like. It's all awesome, it's all worth exploring. And take turns driving, because especially between Florence and Newport is scenic as all **** and also a twisty turny narrow road full of rubberneckers that you must pay attention to.
There are some chances at primitive camping south of Florence if you drive up into the mountains a little, there is none north of there. You gotta pay at an established campground if you want to camp on/near the beach.
Here's some light history reading if you're into that sort of thing -
https://sos.oregon.gov/archives/exhibits/coast-tour/Pages/default.aspx
