There is a Idaho state park on the river at the end of the canyon, it's the best place so far as I can see. Think it's called Hells Canyon SP IIRC They have boat tours leaving from the cg. We stayed there years ago and went by it last year. I don't know if you can get a spot tho, maybe during the week. In October tho it will probably easier to get into the park.
Right now I would certainly avoid WA state except for a day trip in an out.
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