If Acadia has a spine, it is the Park Loop Road. This 27-mile route, much of it one-way along the shoreline, connects the park's most famous sights in one continuous scenic drive, and it is the way most visitors first meet the landscape. From the entrance near Hulls Cove you can climb toward the Cadillac Summit Road, drop to Sieur de Monts and the Wild Gardens, then run along Ocean Drive past Sand Beach and the granite shelf of Thunder Hole, where waves force air and water into a narrow chasm and sometimes produce an echoing boom. Beyond Thunder Hole the road skims Otter Cliff, one of the highest headlands on the Atlantic coast north of Rio, loops past Otter Point, climbs by Jordan Pond and passes the Bubbles before returning north. The route was built in the early twentieth century with the help of philanthropist John D. Rockefeller Jr., who wanted to give visitors access to the scenery without spoiling it, and the stone details and wide pull-offs reflect that care. The drive can be done in an hour without stops, but nobody does it that way: expect half a day with photography, short walks and lunch, and be ready for a slow, polite parade of cars at peak times.
Thunder Hole in practice
It is a natural inlet in the cliffs where incoming surf compresses air and water into a chamber and then releases it with a hollow thud and a plume of spray. The effect is best around the middle of a rising tide and after storms, when large swells roll in, and it can be underwhelming at low tide or on a calm day.
A railed stairway and viewing platform let you look down into the slot, but they close or become unsafe in rough seas, because waves have swept visitors off the rocks, so obey the signs and never climb beyond the barriers. Allow twenty or thirty minutes and then walk along the Ocean Path, which starts nearby and hugs the shore toward Otter Cliff.
Making the drive work
The Park Loop Road has one-way and two-way sections, designated parking on the shoulders in some places, and heavy traffic in July, August and the fall foliage period. Start early in the morning or late in the afternoon, buy your park pass before you arrive at the entrance station, and be prepared for limited parking at Sand Beach, Thunder Hole and Jordan Pond.
The Island Explorer shuttle serves many stops and removes the parking problem, and a trolley tour lets you simply look. If you prefer to drive yourself with commentary, a self-guided GPS audio tour that starts from the visitor center plays stories and directions as you move.
What to bring and where to eat: fill your tank, pack water and a picnic, carry layers and a rain jacket, and plan lunch at Jordan Pond House, where popovers and tea on the lawn are a tradition, or pick up supplies in Bar Harbor. The road is closed to vehicles in winter in places, so check seasonal closures before planning a cold-weather drive.
Binoculars are useful for seabirds, and a field guide or the ranger programs can help identify what you see. On foggy days the drive can still be atmospheric, but the best views vanish, so keep a flexible plan.
What to expect
The experience
A 27-mile scenic loop mostly one-way along the coast with pull-offs at Sand Beach, Thunder Hole, Otter Cliff and Jordan Pond; park pass required.
Best time
Early morning or late afternoon for lighter traffic; mid-rising tide or after a storm for the best Thunder Hole surf.
How long
Three to five hours with stops, a full day with hikes.
Tips
Buy your pass ahead, start early, respect the barriers at Thunder Hole and consider the free shuttle or a tour to skip the parking hunt.
Quick picks
- Best for
- A first look at the park's signature sights in one drive.
- Families
- Excellent; short walks and varied stops keep children engaged.
- Couples
- A scenic road trip with sea air and plenty of pull-offs.
- Pair with
- Sand Beach and the Ocean Path, then lunch at Jordan Pond House.
- Time needed
- Half a day to a full day.
Good questions
How long is the Park Loop Road?+
The loop is about 27 miles, with one-way and two-way sections. Allow at least half a day with stops.
When is Thunder Hole at its best?+
Around the middle of a rising tide and after storms, when waves are strong. On calm days or at low tide it can be quiet.
Do I need a park pass to drive it?+
Yes. Acadia requires an entrance pass year-round, which you can buy at the entrance station, visitor center machines or online.
Can I do it without a car?+
Yes. The free Island Explorer shuttle serves many stops on the island, and trolley and small-group tours cover the loop with a guide.
Is Thunder Hole safe?+
The viewing platform is safe in normal conditions, but it can be dangerous in big seas. Obey closure signs and stay behind the barriers.