Fort Knox and Penobscot Narrows Observatory
See main listingThis 19th-century granite fort sits in Prospect, about an hour west of Bar Harbor. The fort itself is well-preserved and dog-friendly, with staff described as genuinely friendly. But most visitors come for the 420-foot observation tower, a modern bridge structure that's the real draw. You can buy a ticket for the fort alone or combine it with the tower; there's no tower-only option. Admission runs about $6.50 for the fort if you're from out of state. One recent visitor called it "a gem during the drive back from Bar Harbor," and the grounds work well for kids and pets alike.








