For such an iconic and well-traveled thoroughfare, U.S. 1 is surprisingly unknowable. Various sites and sources disagree on when it was established and how long it runs, and pretty much everything except that it passes through 14 states on its way from Key West, Fla., to Fort Kent, Maine. In most of those it offers less variety than you might crave; even Florida is pretty much Florida all the way through.

But if you can hang in there and make it all the way to Maine, you will find, spread out along almost 530 miles, a perpetually evolving panorama. By the time you get to the very end of Maine’s Route 1 (as it is called there), you are sure to feel as though you are no longer in the same state as you were when you first crossed the Piscataqua River from New Hampshire. Perhaps not even the same country.

Land of vacations

There are many Maines, and most get their turn on Route 1. The road enters the state from Portsmouth, N.H., via the Memorial Bridge; the first thing you see as you alight in Kittery is the Maine Sailors and Soldiers Memorial, a striking sculpture commemorating the state’s First World War dead. Shortly thereafter, U.S. 1 dives into Southern Maine as a mile-long, car-clogged gauntlet of outlet stores. Only once you’ve cleared them will you see the sign for the Maine Visitor Center.

The state has long billed itself as “Vacationland,” and you could make the case that the Southern Maine portion of U.S.-1 is just one extended visitor center. Driving it, you get the sense that Mainers have conceded these towns — some of the oldest in the state, dating back to the 17th century — entirely to tourists.

The road here is mile upon mile of motels, antique shops, art galleries, restaurants, ice cream stands, and the occasional miniature golf course or theme park. It’s not all honky-tonk: Downtown Kennebunk, for instance, with its dignified old brick and clapboard edifices, whitewashed Unitarian church with ancient graveyard and flag-festooned lampposts, looks like a set for a Hallmark Channel movie. And sprinkled among most towns are signs that people do, in fact, live here year-round, treading water in a rising tide of tourism: offices, supermarkets, a Civil War monument on the lawn of a gas station.

But for the most part, this stretch of Route 1 seems set aside for what Mainers call folks from away. Those who cling to a cherished image of the place gleaned from a childhood visit, or an old film or novel or Winslow Homer painting, might be struck by a green street sign with a yellow appendix that abuts the road in South Portland: The sign reads “Memory Ln.”; the appendix, “Dead End.”

A ragged coast

U.S. 1 skirts Maine’s largest city, Portland, but not another gauntlet of outlets in Freeport. From there, though, it emerges into a less dense Maine known as Midcoast. Midcoast Maine was mostly settled in the 18th century and built on fishing and shipbuilding, though as you head north, you’ll smell the ocean but won’t see it; this stretch of coastline is quite ragged.

Route 1 completely bypasses some Midcoast towns, but goes right through Thomaston, a picture postcard village that was, incongruously, the home of the state’s maximum-security penitentiary for 178 years. Don’t call it Shawshank, but do stop into the Maine State Prison Showroom (“the prison store” to locals), an old brick shop where one can purchase wooden furniture and toys and even intricately-detailed model schooners, all handmade by some of what one prison official once described to me as “the 900 most dangerous people in Maine.”

The prison itself is now a few miles away, but until 2002 it sat right next to the showroom on U.S. 1. Its former site is now a park; if you’re diligent, you can find a little green enclosure surrounded by an old wrought-iron fence and perched dramatically above the St. George River. Inside, a solitary rock bears a stone slab that simply reads: “In Memory of Those Interred in This Plot.”

There’s a good chance you’ll have to sit in traffic in Rockland, but once you make it through its cramped downtown, the buildings melt away and the ocean jumps right out at you, having grown tired at long last of playing coy.

A lot of things jump out at you along Midcoast’s U.S. 1: In Rockport and Camden, it’s big old ship captains’ houses repurposed as inns; in Belfast, it’s “Passawassawakeag,” the name of the river that promenades beneath you on its way out to sea. And in Prospect, it’s the Penobscot Narrows Bridge, a striking cable-stayed span with two towers that, at 447 feet, stand more than twice as high as the tallest building in Maine. (That would be a church.)

At the top of one is an observatory which affords glorious vistas of land and water and the town of Bucksport, where Route 1 passes right by the grave of namesake Jonathan Buck (1719-1795). His marker bears a stain in the shape of a woman’s lower leg and foot, said to be the manifestation of a curse hurled at Col. Buck by a woman he was burning at the stake as a witch. Two separate plaques next to it explain that this is a myth and that no one was ever executed for witchcraft in Bucksport (or Maine), but I believe the tale anyway, because I want to.

By the time you get to Ellsworth, you’ve driven past countless lobster shacks and piles of nautical knickknacks and motels with names like Yard Arm and Yankee Clipper, so when you see signs pointing to Bar Harbor, you may experience some form of seasickness. The good news is, U.S. 1 doesn’t go there.

The bad news is, you’ve got another 120 or so miles of coastline left.

But it’s different from what you’ve seen heretofore. Very different. You’re now in the third Maine: Downeast.

Open roads and empty fields

Almost as soon as you leave Ellsworth, everything just disappears: The boutiques and antique stores and art galleries and ice cream stands and motels and inns and putt-putt and your cell signal and, most of all, other cars. In their stead is a lot of open road, and empty fields, and pine trees, and water near and distant, and historic homes in various states of deferred maintenance, and, well, a fair bit of good-old-fashioned Maine weird. This is a part of the state where people are relatively few and typically have deep roots and historically haven’t gotten out much except to head out to sea or off to war. I’m not saying that fostered eccentricity; but something did.

You will pass things that, if you don’t feel like stopping the car every few miles, you will want to at least make note of and research later: The large corrugated metal building in Hancock with “Chainsaw Sawyer Artist Live Show” painted on its side; the otherwise nondescript house in Gouldsboro with a Ferris wheel in its yard and a vintage pickup truck parked on its roof; the giant geodesic dome painted like a blueberry in Columbia Falls. In Machias, you might consider following the sign down to Fort O’Brien, where, in June 1775, a deal to trade groceries for lumber went bad and escalated into the first naval battle of the American Revolution. There is a long tradition, up here, of driving a hard bargain.

A large white abandoned house marks the spot in Whiting where U.S. 1 takes a sharp left turn. It soon passes many abandoned things, including barns, shops, boats and a dollop of rock and pines in the bay named St. Croix Island. In June, 1604, 79 French would-be settlers (including Samuel de Champlain) went ashore there and started building. Nearly half died that winter. Today it’s an International Historic Site, the only one in the entire National Park Service system. Its visitor center, a lonely outpost, closes from mid-October to late May, something Champlain no doubt would appreciate.

Many of the handsome brick waterfront buildings in the town of Calais also appear empty, though the entire facade of one, an imposing four-story edifice from 1847, still advertises Dr. Thomson’s Sarsaparilla, The Great English Remedy. Cures When Others Fail!

Dr. Thomson is long gone. So, as an historical marker outside an auto-parts store on Route 1 will tell you, is Washington County’s only synagogue, which once stood at that spot.

More moose than people

Around Danforth, you’ll start to notice empty log trucks heading north. Follow them, and you’ll soon cross over into the fourth of Route 1’s Maines: Aroostook County. Most Mainers just call it “The County,” and don’t know much more about it than you do. The largest county east of the Mississippi, Aroostook is an expanse of forest and farmland the size of Connecticut and Rhode Island combined, with just 67,000 people scattered throughout the whole thing. It’s entirely possible they’re outnumbered by moose.

The first sizable town you hit heading up Route 1 is the county seat, Houlton. Once home to lumber barons, it’s a treasure for connoisseurs of Gilded-Age architecture, and for road nerds: It hosts both the reunion of Route 1 and I-95 (which last crossed paths back in Kittery) just before the latter terminates at the Canadian border, and the only place in the country where U.S.-1 and U.S.-2 intersect, the latter starting in Houlton and ending 2,500 miles west in Everett, Wash.

In a frame on the wall o this a little marble representing Pluto; for the next 40 miles, you’ll pass a 1:93,000,000 scale model of the solar system spaced out precisely along the roadside (earth is the size of a cantaloupe; Jupiter, a giant pumpkin) ending with the sun (sort of) in Folsom Hall, the science building at the University of Maine at Presque Isle. The whole thing was planned, plotted and built by local students, perhaps comforted by the knowledge that the universe, like their county, is mostly empty.

To the border

Outside a little red one-room schoolhouse in Cyr Plantation (in use until 1964), a wooden sign welcomes you to the Saint John Valley — in English and French. Atop it is carved a little tricolor with a gold star in its blue field: The flag of Acadia. A French colony in what is now Canada, it technically ceased to exist when Britain won the French and Indian War in 1763 and expelled its inhabitants, most famously to Louisiana; some, though, sneaked across the Saint John River and have been here ever since. The valley, with its roadside crosses and shrines, and gold or silver painted church steeples, and people who speak English with a thick accent and French at home — and, everywhere, those flags — feels more Acadian than American or Canadian.

After U.S. 1 makes a second sharp left turn at the town of Van Buren, it hews close to the river, which forms the border of the two countries, and which is narrow enough to hit a baseball (or slap a hockey puck) across. You can count the cars parked outside the big churches on the other side; when the water’s low, you could wade to mass. In Madawaska, a paper plant, one of the few remaining in the state, actually straddles the river and thus the border. Pulp produced in Edmundston, New Brunswick, on the Canadian side, is sent through pipes to Madawaska, where it’s turned into pet food bags, magazine pages and labels for prescription bottles. (Even after Covid closed the border, those pipes stayed open round the clock.)

Madawaska is also considered the northeasternmost town in the United States — making it a destination for bikers who take on the challenge (known as the “Iron Butt”) of visiting all four corners of the continental United States in just three weeks — but U.S. 1 keeps going through it, and neighboring Frenchville, before finally coming to a stop in Fort Kent., A marker at a plaza downtown says “2,446 Original Miles,” without explaining that “original.” The plaza, which sits beside the bridge to tiny Clair, N.B., is named “America’s First Mile.” Take that, Key West.

There are people who come all the way to Fort Kent, a rustic place that could pass for Alaska, expressly to see that spot. Few, though, wander over to see the actual Fort Kent, a wooden blockhouse constructed during the Aroostook War of 1838-9, a border dispute between England and the United States that ended without a shot being fired. And thus, Maine’s allotment of U.S. 1, 22 percent of the whole thing, ends just as it began: with a bridge, and a war.

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