Coastal Maine, follow route 1. Bailey's in Old Orchard, Libby's in York(on ocean),Camden Hills(on ocean but no beach 0rocks), Acadia National Park-many campground parks, Sea View, Eastport Maine-on ocean-no swimming just fishing. Bring your passport and hope over to Campanella Island, Canada. If you head inland- Grenville Maine to Moose Head Lake to see moose.
There is a lot to see in Vermont and New York state in the Adirondacks too.
Connecticut and Rhode Island have beautiful campgrounds too.
We are near Cape Cod which has many of our favorite campgrounds. What are your interest and how do you like to camp? That may help with your search.