Like my Yosemite trip, the desire to visit Acadia came from a post card on a refrigerator at work. I couldn't process a place on the East Coast where the mountains touch the sea. We ended up getting a cabin near Bar Harbor, which ended up being significantly less expensive than any B&B options nearby ( seriously, I didn't mind eating out every day simply rom the savings!)
Bar Harbor is famous for having a sandbar show during lowtide, which allows the land and a nearby island to be connected for a brief time. It's a cool experience, and my daughter loved exploring all the critters in the tide pools. We had some great hikes in Acadia, my favorite being Bubble Mountain - which had some spectacular views.