If you have just a few days in the area, plan to spend your nights in Brunswick or Bath. From Brunswick, drive south on Route 24 or Route 123 to explore the Harpswells. Here you'll find a small beach and the bronze Fishermen's Memorial adjacent to the Land's End Gift Shop. Stop for a haddock sandwich at one of the seafood shacks in the area. In the afternoon, take a kayaking trip along the coast. That night, have dinner in Brunswick.
On Day 2, drive south on Route 209 from Bath to Popham Beach State Park, where the Kennebec and Morse rivers meet the sea. Plan to arrive before 10 AM, as the parking lot fills fast. If you arrive at or near low tide, you can explore miles of tidal flats and walk across to Wood Island. You can hike along the beach to Fort Popham, a Civil War-era fortification that is fun to explore. Bring your lunch or pick up a clam or lobster roll near the beach.
You can't complete your time in the Mid-Coast region without an introduction to the area's shipbuilding history. Visit the Maine Maritime Museum in Bath on your third day for a tour of the old shipyard and to see the seafaring art and artifacts that fill this beautiful museum. Stroll through downtown Bath in the afternoon, stopping at Waterfront Park to watch the fishing boats, or sign up for a cruise on the Kennebec River.
Follow the itinerary above for the first three days. On your fourth day, drive north on U.S. 1 to visit Reid State Park, where you can climb up the ledges and watch the waves pound into the rocks below. There are several lodgings in Georgetown right on the water from which you can choose. Heading north on your fifth day, leave U.S. 1 shortly after crossing the bridge at Wiscasset and take Route 27 to Boothbay, where you can browse in the antiques shops and art galleries or scan the horizon for whales on one of the many sightseeing cruises. Spend the night in Boothbay.