We spent almost three weeks in Southwest Harbor and absolutely loved the cottage. It is very bright and airy, and well equipped with modern appliances. The kitchen was well equipped as well, which is a plus for travellers who enjoy cooking, like we do. We were traveling with our 6-month old son, I would definitely recommend this cottage for traveling with young children.
The location in great, it's only a short walk into town and a short drive from Acadia National Park attractions on the quiet side of the island. We enjoyed going to Beal's Lobster Pound down by the pier, getting bread from the Little Notch Bakery and produce from the farmer's market. There is also a liquor store nearby with an interesting selection of American craft beers. There are also many hiking opportunities nearby, including a few easier trails that are great for doing with babies/small children. Echo Lake is also a very short drive away, with a nice beach and water that is warm enough for swimming.
We will definitely consider renting again next time we go down to Mount Desert Island.