You don't say specifically where you are going, but if at all possible, don't miss Cape Breton Highlands National Park at Cape Breton in Nova Scotia, and in particular the Cabot Trail. I did that trip several summers ago, and it is exquisite. Excellent scenic trails throughout the park as well, but every turn of the Cabot Trail is breathtaking, overlooking the ocean on one side, craggy cliffs, and thickly forested hills on the other. We spotted whales, bald eagles, moose and even a huge cayote. Also, if you plan to include Maine, don't overlook Acadia National Park and Bar Harbor.
