Carlsbad Cavern and the “bat flight” , in the bottom of NM is on my list
Kartchner Cavern was nice with a nice campground
TitanMissile silo Museum, near Tucson AZ was interesting
Sonora dessert is good for an evening or morning hike
Central California is hot that time of year, stay in the Sierras or hug the coast and it will be nice. Its crazy, it can be 97deg in San Jose and 30ml to the coast it will be 65 or cooler. Our coast is foggy in the summer.
Redwoods are a must: Sequoia National forest, Calaveras Big Trees, Muir Woods, Redwood National Forest. Any and or all of them are worth some days.
Big Sur is nice, cool, quiet and beautiful coast line.
Yosemite is a must, the valley is grand but the whole park is worth a few days.East of there is Mono Lake with its tufa a neat geological formation. There are a few other things Devils Post Pile, Bristlecone Pines(5000yr old trees) and Bodie a popular ghost town(never been but some day) in that area
We just did Death Valley and it was good but I don’t think you want to do it that time of year, very very hot
San Francisco Cable Car is worth a stop. I personally try to stay out of the big cities but as long as your around its worth doing. Could drive the most crooked street, Lombard, in the US(not with a trailer or I’ll see you on the news). Walk the Golden Gate or just drive.
Lake Tahoe is nice but last time I went thru Emerald Bay(with a TT), that time of year it was extremely mobbed for miles so we just skipped it. Very populated that time of year but get out to some of the smaller lakes up there and enjoy. We did a hot springs 2hr south of there lasts year and it was nice.
Mt Lassen is nice with some volcanic activity and the North side is nice for camping. There has always been snow to play in but maybe not this year, last year was bad and this year hasn’t been any better for snow. Burney Falls just North of there and its grand. I spend 3-7wks a year in this area(Lake Almanor) and we love it: nice and slow, mild climate, no bugs(Ca doesn’t have bugs), great fishing, lots of water activities and my parents have a place up there.
My kids love Lava Beds National on the top edge of Ca. I think they have something like 230 mapped lava tubes, we have done 12 or so and might go back. There is Glass Mt to the South and its full of beautiful obsidian and if you look around you can find pumice, a rock that floats.
There isn’t a bad place on the coast if you can get in, there are to many people in California.Grab some live crab and/or fresh salmon and enjoy. I am a big time fisherman(GradyWhite) so fresh is all we know.
I’m sure I missed a bunch of great places……..