I've done Titus Canyon as well. Recommended. In fact there are a lot of neat roads (4x4 recommended) all over that area, in and out of Death Valley Park. I think I posted here some years back about the catastrophic flat I got from in my 4Runner on the crappy OEM tires it came with from sharp rocks while in this area. The road to Mahogany Flats campground to be specific.
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Mahogany Flats and Thorndike are both cool (literally - I was freezing in my tent in June in Death Valley, because 8000') camping areas. Be sure to checkout the Wildrose Kilns on the way up the road.
Another cool area where 4WD is a must is just outside of Sisters, OR. I've centered the area on Link Lake:
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But there are several lakes and ponds in the area, and at least when I was there during the week in I think May, I had everything all to myself. I reiterate 4WD, and frankly, on weekends, I wonder what people do, because most of the trails I was on were no wider than my 4Runner, and very few clear areas to pullout if two vehicles meet. I think I may have some video from when I used to use a dashcam and will post it if I can find it.
Fort Stevens State Park in Oregon is cool if you like driving on the beach, literally feet from the ocean. You can drive right up to the Peter Iredale shipwreck.
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From our time doing Operation Godfather, Charby can confirm that there are very cool "roads with a view" all over Moab.
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Going to the Sun Road in Glacier National Park is awesome. It can be very crowded during the season though.
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Bonners Ferry, ID to Whitefish MT is beautiful.
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