Fort O’Brien State Historic Site
Maine Historic Site

Fort O’Brien State Historic Site

88 Dunns Point Lane, Machiasport, Maine 04655
Available Activities
  • Sightseeing

🏆🏆🏆🏆🏆 First Naval Battle of Revolution — Site of the FIRST naval battle of the American Revolution — June 12, 1775 (before Bunker Hill!)

Fort O’Brien State Historic Site in Machiasport preserves the earthworks of Fort O’Brien — site of the first naval battle of the American Revolution! On June 12, 1775 (five days before Bunker Hill!), Machias patriots captured the British armed schooner HMS Margaretta in the “Lexington of the Sea.” Local lumbermen, armed with pitchforks and muskets, rowed out in lumber boats and overwhelmed the British crew. The battle proved that colonial resistance wasn’t limited to Massachusetts — even the remotest Maine coast was ready to fight.

Visitor Information

DetailInformation
LocationMachiasport, Washington County, ME
Entry FeeFree
BattleFIRST naval battle — June 12, 1775!
Nickname“Lexington of the Sea”!

Frequently Asked Questions

What was the “Lexington of the Sea”?

Five days before Bunker Hill, Machias lumbermen attacked HMS Margaretta with pitchforks! The captured vessel became one of the first ships in what would become the Continental Navy. Machias patriots proved that Revolution wasn’t just a Boston phenomenon.

About Fort O’Brien

Fort O’Brien State Historic Site in Machiasport preserves the remains of fortifications overlooking Machias Bay — site of the first naval battle of the American Revolution (June 1775), even before Bunker Hill. Local patriots captured the British armed schooner HMS Margaretta in a daring raid. The earthworks of the 1775 fort and later War of 1812 defenses remain visible.

Things to Do

Exploring the historic fort earthworks, learning about the first naval battle of the Revolution, enjoying spectacular Machias Bay views, and visiting the nearby Machias Historical Society. One of Maine’s most historically significant but least-visited sites.

Make it a road trip: Pair a visit with Roques Bluff State Park (a short drive away) or Roque Bluffs State Park (a short drive away).

⚓ Visit Fort O’Brien SHS

FIRST naval battle of the Revolution — “Lexington of the Sea” June 12, 1775!

📍 Maine BPL

Wildlife & Nature

Fort O’Brien SHS — site of the first naval battle of the American Revolution (June 12, 1775) — the Battle of Machias, where local patriots captured the British armed schooner HMS Margaretta. The site’s Machias River, coast, and forest support bald eagles, ospreys, and harbor seals.

Nearby Attractions

Machiasport — adjacent. Machias — 5 miles upstream — “Blueberry Capital of the World”. Bold Coast — 15 miles east.

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Last updated: May 14, 2026

Park Location

88 Dunns Point Lane, Machiasport, Maine 04655