🌤 Weather at Fort Constitution State Historic Site by season
| Spring | Summer | Fall | Winter |
|---|---|---|---|
| 25–66 °F | 54–80 °F | 31–72 °F | 16–38 °F |
Each range runs from the coldest monthly average low to the warmest monthly average high in that season (1991-2020 climate normals), measured at Greenland, 7 mi away, elevation 95 ft. Conditions at the park can differ from the station, especially where elevation differs — check a forecast before you go.
🏆 First Strike of the Revolution — Site of the FIRST offensive military action of the American Revolution — December 14, 1774 (4 months before Lexington!)
Fort Constitution State Historic Site in New Castle preserves the remains of Fort William and Mary — site of the first offensive military action of the American Revolution! On December 14, 1774 — four months before Lexington and Concord — 400 New Hampshire patriots stormed the British fort and captured 100 barrels of gunpowder and 16 cannons. This was the first time colonial forces physically attacked and overpowered a British military garrison. The stolen gunpowder was later used at Bunker Hill. The fort was renamed “Fort Constitution” after independence.
Visitor Information
| Detail | Information |
|---|---|
| Location | New Castle, Rockingham County, NH |
| Entry Fee | Free |
| Battle | Dec 14, 1774 — BEFORE Lexington! |
| Captured | 100 barrels gunpowder + 16 cannons! |
| Impact | Powder used at Bunker Hill! |
Frequently Asked Questions
Was this really before Lexington?
Yes! The raid on Fort William and Mary on December 14, 1774 was the first time colonists physically attacked a British military installation. Paul Revere himself rode from Boston to warn New Hampshire patriots that the British were sending reinforcements. The 100 barrels of stolen gunpowder helped arm the colonial forces at Bunker Hill six months later.
Was this before Lexington and Concord?
Yes — on December 14, 1774, 400 Patriots stormed Fort William and Mary, overpowering the small British garrison and seizing 100 barrels of gunpowder and 16 cannons. This occurred four months before the “shot heard round the world” at Lexington (April 19, 1775). The stolen gunpowder was later used at the Battle of Bunker Hill. Paul Revere’s ride to Portsmouth to coordinate the raid is largely forgotten.
More parks nearby: Fort Stark State Historic Site is a short drive away, while Odiorne Point State Park lies a short drive away.
⚔️ Visit Fort Constitution SHS
FIRST offensive attack of the Revolution — Dec 14, 1774, before Lexington!
Insider Tips
Pre-Revolution raid: Fort Constitution (originally Fort William and Mary) was raided by Patriots on December 14, 1774 — four months BEFORE Lexington and Concord. Pro tip: Paul Revere rode to Portsmouth to warn that British reinforcements were coming — his lesser-known ride predated his famous one. First shots: Some historians argue this raid was the first overt military action of the American Revolution.
Best Time to Visit
December 14: Anniversary of the 1774 raid. Summer: Coastal setting at its best. Fall: Clear ocean views. Year-round: Fort ruins accessible.
Wildlife & Nature
Fort Constitution State Historic Site — at New Castle Island at the mouth of Portsmouth Harbor — preserves the ruins of Fort William and Mary, site of one of the first overt acts of the American Revolution. On December 14, 1774 — four months before Lexington and Concord — 400 New Hampshire patriots stormed the British fort and seized gunpowder and cannons. The fort’s harbor location provides views of Portsmouth Harbor Lighthouse and the Isles of Shoals. Common eiders and harbor seals are seen in the harbor.
Nearby Attractions
Portsmouth — 2 miles west — has a historic downtown, Strawbery Banke Museum (10-acre living history museum), and waterfront restaurants. New Castle — adjacent — is the smallest town in NH. Isles of Shoals — 6 miles offshore — have Star Island conference center. Odiorne Point State Park — 3 miles south — has the Seacoast Science Center.
🐾 Dogs & Pets at Fort Constitution State Historic Site
- Pets allowed? statewide rule
- Many NH state parks allow pets year-round, but policies vary by park and some parks prohibit pets entirely.
- Leash rule statewide rule
- Standard or retractable leash not greater than 6 feet required; animals may not be left unattended.
- Beaches & swim areas statewide rule
- Pets are prohibited at beaches and designated swim areas seasonally from May 1 through September 30.
- Cabins & lodging statewide rule
- Pets are permitted at 13 campgrounds (including Bear Brook, Coleman, Greenfield, Lake Francis, Milan, Mollidgewock, Moose Brook, Pawtuckaway, Pillsbury, Sunapee and Umbagog); cabin/yurt rules vary by park — check before booking.
- Statewide exceptions statewide rule
- Monadnock, North Hampton State Beach, Odiorne Point and most of Rhododendron State Park prohibit pets year-round; Crawford Notch, Franconia Notch and Mount Washington allow pets only on hiking trails and designated dog-walk areas.
Are dogs allowed at Fort Constitution State Historic Site?
Many NH state parks allow pets year-round, but policies vary by park and some parks prohibit pets entirely. Individual parks can post stricter rules — check signage on arrival.
Rules verified July 2026 via nhstateparks.org. More: New Hampshire state parks guide · Dog rules in all 50 states compared
