It's been years since I was in Maine, but it's still one of my favorite states (sigh). I love the York area--York Beach (be sure to visit Cape Neddick i.e. "Nubble" Light--one of the most photographed lighthouses in the country). The Goldenrod restaurant (if it's still there) had the best breakfasts.....
The whole coastline is gorgeous--Kittery, Two Lights State Park, Portland Head Light, etc. (Years ago I designed cross stitch patterns based on my photos of some of the lighthouses there. You can find them on my website: http://www.art-rageous.net/CrossStitch.html )
It gets more and more rugged the further north you go. Near Calais (up near the Canadian border) there are (used to be?) some wonderful natural beaches to walk on.
My advice would be to stay off the interstates and explore the coastal roads and little towns.
There are several artists' colonies along the coast--one is/used to be at Perkin's Cove which is near Ogunquit.
Wish I were going with you!
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