Acadia National Park in Maine is mostly located on Mount Desert Island, which is separated from the mainland by a small strait. Unlike many of the other national parks, the entire island is not protected, so there are towns, houses, and businesses on the island. This actually makes for a richer experience than just enjoying Acadia's natural treasures.

Another unique feature of Acadia is that the park has 45 miles of carriage roads (open to hiking, biking, and horses) which were designed by John Rockefeller for everyone to enjoy the countryside. These carriage roads are signed separately from the trail system. Instead of having names for the roads, you navigate them point to point, in the direction of where you are going.

Acadia's rocky coastline is a huge draw for most visitors. There are tidepools at low tide, and the Bass Harbor Lighthouse is one of the most photographed in Maine. Several paths lead to the ocean or near it - the Ocean Path is a very easy walk that runs right along the coast (but very close to the road).

Another draw to the national park is Acadia's mountains. Cadillac Mountain has a paved road going up, and lots of parking, so it is predictably the most popular mountain. Acadia Mountain on the east side of the park has similar views, but a strenuous, short hike up to the top leaves the crowds behind. The Beehive and the Precipice trails go up to the top of mountains, but neither one is really a hike - you have to navigate fixed iron ladders and rungs on exposed ledges to get to the top.

To get away from the crowds, explore one of the other areas of the park, such as the Schoodic Peninsula on the mainland, or Isle du Haut.
Unlike other national parks, Acadia is very civilized. Towns are located right outside the park boundaries for shopping, sleeping, and eating. There are several roads through the park, and much of the park is accessible either by car or boat. Several areas of the park are isolated from the main part on Mount Desert Island, such as the Schoodic Peninsula and Isle du Haut.

Cadillac Mountain is the highlight of many trips. Hikers can take a trail up to the top of the peak, or you can ride a bike to the top on the road. Most people drive up to the top.

Acadia is best in summer and fall, but that is also when it is most popular. Try coming in October for the fall colors and to miss most of the crowds. One thing to note is that the park service does start closing out parts of Blackwoods campground (open all year, but not all of it, and in winter it goes very primitive) quite early, which could leave you without a tent spot in October. Perhaps they will reconsider this policy.