There are also boats to Monhegan from New Harbor and Boothbay Harbor. It might be easier to go from Boothbay via train to Wiscasset and taxi or Uber to Boothbay Harbor, although the boat trip is a bit longer. But the Balmy Days boat is large and comfortable. The Port Clyde boat is the mail boat for the island so runs year round. The other boats are seasonal.Rockland is also not far from Port Clyde, the departure point for the boat to Monhegan Island, which I recall from an ill-fated attempt to visit the island years ago.