Explore Fort Knox Maine State Park

Fort Knox MaineMilitary fans, history buffs, and anyone who enjoys eye-popping views will enjoy a visit to Fort Knox Maine State Park. At more than 150 years old, it is Maine’s largest historic fort and one of the best-preserved military fortifications in New England.

Fort Knox State Park is located on the west bank of the Penobscot River, at the Penobscot Narrows, in Prospect, Maine. The attraction is only ten minutes or so from our Maine Coast bed and breakfast, Captain Nickels Inn.

The fort was named after Major General Henry Knox, first U.S. Secretary of War. Confusingly, his name was also used for Fort Knox in Kentucky, famous for sitting next to the country’s gold bullion depository.

Fort Knox in Maine was constructed between 1844 and 1869 to protect the Penobscot River Valley against a possible British naval attack. The exceptionally well-preserved granite fortification is an outstanding example of 19th century engineering.

Visitors to Fort Knox will also have access to the Penobscot Narrows Observatory. The observatory is located on top of the Penobscot Narrows Bridge, some 420 feet above the river.

Visiting the Fort

Fort Knox Maine Rodman cannonThe Fort Knox Historic Site includes over 144 acres to explore. Go on a self-guided tour or join in on one of the docent-led free interpretive tours.

The massive and well-preserved granite fortification is very impressive, with many unique architectural features. The fort also has a rich and fascinating history, even though it never saw battle.

Tour the fort and get a taste of what it was like for the soldiers that lived and trained here during the Civil and Spanish American wars. You’ll see 10 inch and 15-inch Rodman cannons as well as Howitzer anti-personnel guns, complete with original barrels and carriages.

Stop by the Visitor Center to learn more about the fort’s history through photos and replicas. The fort is also the site of many special events throughout the year, including concerts and a variety of living history events.

Penobscot Narrows Bridge and Penobscot Narrows Observatory

Penobscot Narrows ObservatoryNo visit to Fort Knox is complete without also taking the elevator up to Penobscot Narrows Observatory, included with admission to the fort.

Penobscot Narrows Observatory has the distinction of being the tallest public bridge-observatory in the world. It’s even taller than the Statue of Liberty!

The Penobscot Narrows Bridge is an innovative and award-winning structure on its own – but just wait ’til you get to the top. 360 degree, 100-mile views of the Penobscot River Valley await you. Be sure to bring along your camera and a sense of wonder.

Fort Knox Maine Historic Site

740 Fort Knox Road, Prospect, Maine 04981

The park grounds are open from 9am to sunset, all year ’round. Visit the fort website for current Fort and Observatory hours, pictures, and other information.

Updated March 2023



And we can’t wait to share it with you!  With so much to do, one night is never enough. Stay two or more nights and enjoy a discounted stay.  No code needed – it is automatically applied when you book direct.


Want a little extra room? Our newest room, renovated in 2023, is the Willard Room. It is located on the third floor with partial water views, a separate sitting room, and a jetted walk-in shower.