We camped at the Mt. Desert Narrows Campground for a week in August of 2003. What an excellent place to stay. Someday we will absolutely go back. Our highlights: bike ride on the carriage roads of Acadia, walking around Bar Harbor, dining in Bar Harbor - great place that has best clam chowder and blueberry pie with a 2nd floor dining room that overlooks harbor...forgetting name, but it is on a corner, we did paint pottery thing one day, my DH rode his bike down from the top of Acadia, hiking around Acadia, we also did the horse drawn wagon ride of the carriage trails, very enjoyable.
Oh, another thing that was very cool...at low tide, you can cross over the "harbor" on a land bridge to an island. We really enjoyed doing this. We also walked the residential neighbors of Bar Harbor too. We really loved visiting there.
Another evening we took a shuttle to a very small harbor town...forgettin the name, and had our best meal at a small but very upscale/gourmet restaurant/bar. Loved it.
We didn't use a pool while we were there. Way too chilly and rainy, but we still had a blast...we also now own raingear emblazed with Bar Harbor all over it.
One thing that I really thought was great - you do not need a car. They have a shuttle/bus system that has something like 6/7 different routes. Our campground was one of the pick up points. The main hub for the shuttles was Bar Harbor. It was sponsored by LL Bean.
Happy planning. Have some blueberries for me.
Pam