Anything will fit but you will have to drive slow and be careful of the trees
No size restrictions for the drive, but pullouts may be a different issue
Seen a full class A hauling a car behind it, might be some right areas, just wait for oncoming lanes to clear and get thru just fine.
There is no size restrictions for the avenue
I'm not real sure, but I have seen very large RVs on the Avenue of the Giants.
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