After lobster (and maybe L.L. Bean), the icon most associated with the coast of Maine is the lighthouse. There have been scores and scores of books, paintings, photographs and trinkets devoted to these towers that dot the coast, rising up above the low-slung Cape Cod houses that characterize the man-made landscape. Lighthouses speak to our nautical history, a remnant of the days when most transportation was by sea and often treacherous.

But far less has been written about the forts of Maine, which also served a vital, protective role in the state’s history. They, too, speak to Maine’s early and middle history, and actually span a period far greater than do our lighthouses.

Architecturally, most are marvels of the pre-industrial age. Before steam and diesel power, how were the huge granite blocks set in place on difficult-to-access sites and at such precise angles? And most were built in the midst of conflicts, or at least during threats of conflict, giving the construction work an urgency that must have made the work dangerous.

But the work was done well, because most of Maine’s forts are still here.

In fact, so many of our forts remain, in some form or another, that a book recounting all of their stories—if forts are defined broadly as “defense sites”—would resemble an encyclopedia.

Instead, in The Forts of Maine, historian and retired educator Harry Gratwick, who summers on Vinalhaven, wisely narrows his focus to a dozen, and organizes them by region.

Gratwick writes about a fort along the Canadian border and one at the southern entrance to Maine, three dotting Portland Harbor, two on the Kennebec River, two on Lincoln County’s coast, and three rimming Penobscot Bay.

Gratwick illuminates the forts’ histories through anecdotes. Did you know that Abraham Lincoln’s first vice president was stationed at Fort McClary in Kittery while he was “a heart beat away” from the presidency?

Or that during that same era, a Confederate mariner tried to steal a Union cutter from Portland, but was captured by “two armed steam vessels filled with irate citizens”? The Confederate raider and his crew of 22 were imprisoned at Fort Preble in the harbor, Gratwick tells us.

And even here, there’s a dose of irony to enrich the tale—some credit for getting Congress to approve building Fort Gorges, also in Portland Harbor, is given to former Secretary of War Jefferson Davis, later more famous as the president of the Confederacy.

These impressive and long-lasting stone edifices like Fort Gorges represented a new level of defense, following the devastation of the fledgling nation at the hands of the British during the War of 1812. Granite from Mount Waldo in Frankfort on the Penobscot River was used in building Fort Gorges, ensuring it would withstand fire and cannonballs.

Built in the period from 1816 to 1864, these “Third System” forts proved valuable during the Civil War, but were outmoded as weaponry evolved during and after that conflict.

Castine, one of my favorite places to visit for a day’s walk, provides historically rich subject matter for Gratwick. A bone that was fought over by the French, English, Dutch and fledgling Americans, the little island-like peninsula has the remains of several forts that attest to the several centuries of conflict.

The author uses Henry Mowat, a British captain, to tell part of the story of the Castine forts. Mowat is infamous for overseeing the destruction of Falmouth—present-day Portland—during the American War of Independence. Four years later, Mowat was in charge of defending the British stronghold Fort George against the large American flotilla that sailed north from Boston in the summer of 1779.

The American force failed for reasons tied to its own poor command decisions, but Gratwick explains how Mowat used his ships and their cannons to successfully defend the town.

The Forts of Maine is well-illustrated with contemporary photos, historic sketches and maps illuminating the settings in which these wars and rumors of wars played out. Coupled with Gratwick’s use of people to tell the stories of these edifices, the book provides a window through which we can learn about the conflicts that shaped our coast and our state.