The day's main event in the Thousand Islands is sunset. On Wellesley Island, it's best viewed from the porch of the Wellesley Hotel, an old frame resort built in 1903. Tall Victorian houses cast deep shadows that reveal elaborate gingerbread motifs. Playing cards are shuffled on open-air porches. There's the thwack of screened doors, the clang of a bicycle bell, the squeak of a porch swing.

Across the town green on the St. Lawrence Seaway, freighters as big as islands slide by, sterns emblazoned with their ports of registry--Dubrovnik, Montreal, Genoa, Caracas. Tethered boats bump against their docks when the wakes reach shore. The day's last speedboaters dart toward piers on distant islands. If it all seems a bit old-fashioned, well, the Thousand Islands are an old-fashioned sort of place. This placid archipelago, which stretches in a 60-mile chain that marks the border between New York and Ontario about three hours southwest of Montreal, first blossomed in the late 19th century as a summer resort for a new American elite. Like the summer citizens of such places as Cape May, Jekyll Island, and Asheville, they came to these islands to play croquet, ride bicycles on paths along the seaway, and share gossip.

In time, these new American millionaires moved on. And although much of the grand architecture they built hasn't survived them, many lovely old homes remain. So, too, does the tranquillity they sought in the hot summers. Of the 1,800 or so islands, just three main ones--Wellesley, Hill, and Wolfe--are accessible by car. In winter, the power is turned off on most of the islands. The only way to get to them is by ice skating or walking-carefully--across the frozen river.

The Castle Love (Almost) Built
A dark stone castle looms on the horizon across from Alexandria Bay, now home to kitschy tourist shops and pinball arcades. The castle is a jumble of peaked roofs, chimneys, and spires that resembles a whole city skyline rather than just a single building. This is Boldt Castle, reachable via one of the faux paddleboats that cross its moat (the St. Lawrence) and erected by George Boldt, a Prussian-born immigrant who co-owned the Waldorf-Astoria Hotel. He bought what was then known as Hart Island, reshaped it as a heart (and changed its spelling accordingly), and began building a six-story, 120-room fortress.

By 1904 his castle complex included a miniature Arc de Triomphe, a defense tower, and a Swiss chalet-like folly. But when Mrs. Boldt died suddenly, George became so despondent that he halted construction, never returning to the island he'd fashioned as a valentine for his wife. Today it's the region's biggest tourist attraction. Most of the rooms in Boldt Castle are empty, bereft of the iron birdcages and tufted, overstuffed furniture of its day. The rusty spokes of the unfinished dome dangle like the legs of a giant spider over the entryway.

It was another George, George Pullman, who first brought prominence to the Thousand Islands when he built his summer home here, a shingled stone mansion with a conical tower. And when, in 1873, he entertained President Grant and General Sheridan on the island he named for himself, the media frenzy that followed helped define the region as a place of power and beauty.

As America's industrial revolution gathered steam, fortunes were made in the manufacturing centers of upstate New York-Syracuse, Buffalo, Binghamton, and Utica--and farther afield, on the shores of the Great Lakes. It wasn't just the industrialists who got rich; so did the men who sold goods and services to the factory towns--the likes of H. J. Heinz, the Pittsburgh condiment maker, and J. Heineman, founder of Buster Brown shoes. All were self-made men who came from humble, sometimes immigrant, backgrounds, and their summer escapes were likewise to places of their own making. Newport and Sara toga, after all, were the provinces of the more established families of the day--the Vanderbilts, the Astors, and the Rockefellers.

George Boldt's windows offer views to a kingdom of islands, many with their own kinds of castles--expansive clapboard dwellings with airy porches and towering stone chimneys, noble shingled mansions, daring A-frames. From the deck of a tourist boat, visitors can approach--though not dock at--these retreats, most of which are still privately owned. Zavikon Island, home to a voluminous white clapboard house ringed by an open porch, is really two islands joined by a tiny suspension bridge--the world's shortest international bridge, locals claim--linking one piece of land in the United States with another in Canada. Casa blanca, a Cuban plantation-style house, is protected by gargoyles meant to ward off evil spirits--not the supernatural kind, but the ones that haunted this region during Prohibition.

Ferry Tales
At the century's end, the Thousand Islands were bustling. As many as 20 trains a day came in and out of Clayton, the region's unofficial capital, depositing passengers only a few feet from the waiting steamboats, which would ferry them among the islands. Hotels appeared--great resorts like the Wellesley, with its wide porches and large public rooms; these were places a newly minted millionaire went to be seen.

By the '30s the islands' luster had faded. Perhaps it was their very success that did them in. "It was the middle class," the proprietress of the Wellesley tells me as she leans over the reception counter. When "those people" showed up, the wealthy found their exclusive preserve compromised. Moreover, once the automobile caught on, people no longer needed to vacation in one place, especially one as difficult to reach as an island.

A series of devastating fires was the final blow. During the Great Depression, many mansions were set ablaze by owners eager to collect the insurance money. Even today, the threat of fire hangs over the islands. Peter Eppolito, a young bartender at the Clipper Inn restaurant in Clayton, recalls one downtown blaze in the '70s. "The wind was so strong coming off the St. Lawrence--as it often is--that burning shingles were landing in our yard several blocks away. We were lucky our house didn't catch."

These days Clayton is a quiet, dignified town on the Seaway Trail, a 454-mile scenic highway that follows the bank of the St. Lawrence River. Classic neo-Romanesque buildings line the downtown streets. The namesake salad dressing is still concocted at the century-old Thousand Islands Inn on Riverside Drive, though there seem to be as many recipes and places of origin for the dressing as islands.

Happily Ever After …
Today wealth has returned to the Thousand Islands. American and Canadian franchise kings, doctors, lawyers, and professional athletes have established their island compounds, though their privacy is regularly invaded by the boat guides."Riding on this very boat with us are the recent husband-wife purchasers of Tom Thumb Island," one announces, referring to the smallest island in the chain. The five-foot-square parcel meets the region's official definition of an island, since it sustains at least one tree and is always above water.

Near a different island, people on the tour boat rise to take snapshots of a shingled mansion dating from 1915. The guide describes the yard of another house as a sculpture park. "All of those wooden creations you're seeing--bears, eagles in flight, figures at play--were sculpted by the owner using only a chain saw."

Most year-round residents live more modestly in the mainland towns. Sam Williams, for instance, mans the visitor's center at the Tibbetts Point Lighthouse at Cape Vincent, on the western edge of the archipelago. From his vantage point I can see what "geography" can really mean--here a great lake feeds into a great river, which leads to an ocean. From Williams's desk, there is the infinite expanse of Lake Ontario, its flawless complexion marred only by faraway freighters sending up wisps of smoke.

"I'm not from around here originally," says Williams, looking very much like a lighthouse worker with his gray beard, pipe, and brimmed cap. "My wife grew up in the area, and after World War II, she took me here to meet her family. The moment our car came over this hill and I saw this, I said to myself, 'Yes--this is where I want to spend the rest of my life.' "