June: Early June is Acadia before the July rush: fresh green, cool ocean air, and lupine blooming across Mount Desert Island. Cadillac sunrise still needs a vehicle reservation.
October: Fall color on Mount Desert Island peaks in early to mid-October: maple red against granite and ocean. Cadillac vehicle reservations run through October 25 in 2026.
Permits and reservations
No reservation is needed to enter the park, but this park does not take cash. A separate $6 vehicle reservation is required to drive Cadillac Summit Road, and all campsites must be reserved online ahead of time.
Cadillac Summit Road vehicle reservation: Required to drive up Cadillac Mountain (sunrise and daytime slots). 30% of reservations release 90 days ahead and 70% release 2 days ahead, both at 10 a.m. ET. Motorcycles need their own reservation.
Campgrounds (Blackwoods, Seawall): All campsite reservations must be made online in advance.