Fort Knox, Maine — History & Visitor Guide

Fort Knox (Prospect, Maine)

Prospect · Maine · Civil War

Quick BriefBuilt between 1844 and 1869, Fort Knox was the first fort in Maine built entirely of granite. This Third System defensive structure overlooks the Penobscot River and was used as a garrison for Union troops during the Civil War. Though manned during both the Civil War and Spanish–American War, the fort never saw combat. The state of Maine purchased it in 1923 for $2,121 and has administered it as a state historic site since 1943.

Civil WarCoastal defenseOpen to visitors

History & Significance

During the War of 1812, a British naval force defeated an outnumbered American force in the Battle of Hampden, then looted both Hampden and Bangor. The Aroostook War of 1838-1839 revived anti-British feeling and concern over the vulnerability of the region to another attack.

The response was inclusion of the Penobscot in the Third System of coastal fortifications and construction of a large, expensive granite fort at the mouth of the Penobscot River. Joseph G. Totten, the Army Corps of Engineers' foremost fortification engineer, designed the fort.

Built between 1844 and 1869, it was the first fort in Maine built entirely of granite. The Civil War garrison was less than fifty troops.

Congress appropriated $3,200 for a controlled minefield laid in the river during the Spanish–American War. In 1970 the fort was designated a National Historic Landmark. Today the fort stands as one of New England's best-preserved mid-nineteenth-century coastal fortifications.

Key Facts

StateMaine

LocationProspect

Established1844

Decommissioned1923

War / eraCivil War

Current statusState or National Park

Coordinates44.56619444, -68.80241667

NRHP reference69000023

Map

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🧳 Visiting

What you’ll see when you visit:

Granite seacoast fortification with well-preserved Civil War-era architecture
Period cannons and military equipment on display
Scenic location overlooking the Penobscot River
Underground casemates and powder magazines to explore
National Historic Landmark with preserved 19th-century defense structures

Best time to visitSpring (May-June) and fall (September-October) offer mild temperatures and lower humidity; summer brings warmth but can be crowded, while Maine winters are cold and snowy.

Getting thereFly into Bangor International Airport (BGR), approximately 27 kilometers south of Prospect, then drive north to reach the fort.

From the nearest major airportBangor International Airport (BGR)🚗 24 mi by road⏱️ ≈ 42 min drive

Fort Knox (Prospect, Maine)

History & Significance

Key Facts

Map

🧳 Visiting

Sources

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