A tour of Marblehead’s newly accessible Fort that was established in 1644 (over 375 years ago !) and enlarged and/ or renovated in c.1743, 1775, 1794, and 1864 — with 2, 12, 18, then 24 cannon around its perimeter. Twelve different military engineers were involved in those renovations. Named Fort Sewall in 1800, its most famous moment came soon afterward, on April 3, 1812, when it saved & harbored the USS Constitution. It became a recreational area in the 1890s and an official town park in 1922.