Permanent claim record · Mackinac Island, Michigan

Fort Mackinac was British-built in 1780 during the Revolutionary War, transferred to the US after Jay's Treaty in 1796, and remained an active US Army post until 1895 — one of the longest-serving frontier fortifications in American history.

Verified\u00b7 1780-01-01

Raw value (vault-stripped)

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Predicate	trivia.fact
Subject	Mackinac Island, Michigan (place)
As of	1780-01-01
Status	Verified
Source	West Michigan Tourism: Attractions, Landmarks & Regional Highlights — Perplexity Deep Research (March 2026) (trust 6.5/10)
Reference	—
Document hash	pending evidence-pack link
Provenance chain
Claim ID	25f680dc-63b4-49d1-8ee2-c8564de4ccf0