You are limited to the 4 main campgrounds in an RV. https://www.nps.gov/shen/planyourvisit/campgrounds.htm
Yes, only in the designated areas. Some are first come first serve; others are registration only. One of the areas is near big Meadows.
Yes in some Designated areas only.. you can register online for the same on the Shenandoah Website.
Yes
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