Fort O’Brien State Historic Site
Maine

Fort O’Brien State Historic Site

Available Activities
  • Photography

๐Ÿ†๐Ÿ†๐Ÿ†๐Ÿ†๐Ÿ† First Naval Battle of Revolution โ€” Site of the FIRST naval battle of the American Revolution โ€” June 12, 1775 (before Bunker Hill!)

Fort O’Brien State Historic Site in Machiasport preserves the earthworks of Fort O’Brien โ€” 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 โ€” even the remotest Maine coast was ready to fight.

Visitor Information

DetailInformation
LocationMachiasport, Washington County, ME
Entry FeeFree
BattleFIRST naval battle โ€” 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 โ€” 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.

โš“ Visit Fort O’Brien SHS

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

๐Ÿ“ Maine BPL

Last updated: May 9, 2026

Park Location