Just before Mrs. Astor entered the ballroom of Beechwood, her Newport mansion, for Christmas dinner, she introduced me to her oldest son, John Jacob IV. As soon as he slipped beyond earshot, I framed the question that seemed so impolite but so, well, obligatory. "He sinks with the Titanic, right?"

        The Grand Dame of the Gilded Age nodded but recommended that I keep his fate to myself — atleast until after dinner. "We wouldn't want to dampen his appetite." Outside, the Rhode Island air was bracing. And if the date on my digital watch insisted that I was in the final December of the 1900's, within the poinsettia-rich opulence of Beechwood, time was streaming in reverse.

       It was 1891, and the Astor family — or, rather, actors playing them [see photo] — was celebrating what they called St. Nicholas Day with nearly 100 guests, including myself and my fiancée, Abby. That our real hosts were long dead was a technicality. This is Newport at Christmas — a fantasy, to be sure, but fantasy fits hand in white glove in this living theme park of America's past.

       From harbor to ocean, the layers of Newport's history are all clearly visible, touchable and tourable. Having spent parts of every summer since 1994 here with Abby, who was born in Newport, I've seen, touched and toured with continuing pleasure. Over the years we've wandered through the mansions on Bellevue Avenue and meandered the narrow, Colonial streets closer to the harbor. We've worshiped in Touro Synagogue, the nation's oldest standing temple, and in Trinity Church, built in 1726, on Spring Street at Queen Anne Square where George Washington's pew remains.

       We've played on the grass courts behind the International Tennis Hall of Fame and Museum, and, like Edith Wharton and Henry James a century ago, browsed the stacks at the Redwood Library and Athenaeum, America's oldest lending library. What we had never done was see Newport in winter. What we found was a town we hardly knew, a Newport defined very much by the pleasures of what wasn't there — the hectic summer pace of the tourist crowds. Newport takes its Christmas seriously.

       The annual Christmas in Newport festival, begun in 1971, now extends from the last weekend of November to New Year's Eve, with scheduled events ranging from concerts, lectures and recitals to crafts, mansion tours and holiday-themed visits with the Astors as part of Beechwood's Victorian Christmas program. Enter Newport this time of year, and a luminescence you can't find in summer quietly embraces you. Under the festival's aegis, the downtown harbor is bathed in white light, as is the civic tree at the entrance to the harbor on Bowen's Wharf. Throughout town, storekeepers and residents are encouraged to place electric candles in their windows.

       After dark the city is united in a pale, antique glow. Because we were used to Newport's summer hurly-burly, the weekend itinerary we had jammed together from the Christmas in Newport Web site included a concert of carols, a lecture, visits to four mansions, a holiday baking class and a "Messiah." We would also have included the traditional reading of "A Visit From St. Nicholas," better known as "The Night Before Christmas," but we were a week early. Newport makes at least partial claim to Clement C. Moore, the biblical scholar from Manhattan who may or may not have written the poetic chestnut that sired America's image of Santa Claus.

       Moore retired to Newport and died there, at 83, in 1863. His imposing Victorian cottage, now converted to condominium apartments, stands on the corner of Catherine and Greenough Streets, just off Bellevue Avenue.

       Perhaps it was Moore's spirit that lured us to choose the nearby George Champlin Mason House, a bed-and-breakfast inn, as our winter-weekend base. Mason, a prominent local architect and writer, built his family's Swiss-style house, which he originally called Woodbine Cottage, in 1873. It is filled with Victorian charm right up to its 11- foot ceilings, just the right height to accommodate the 10-foot tree that its proprietors, Harlan and Sheila Tyler, had placed in the archway of their living room — for easy viewing from the cozy library. The Tylers assigned us to one of the three spacious upstairs rooms with a working fireplace (there are also two suites — but without fireplaces).

       Late to arrive — we hit heavy traffic on the ride up from our home just south of Philadelphia — Abby and I raced for the door as soon as we'd dropped off our luggage. We had already missed the evening program of "Carols, Stories and Good Humor" at the Congregational Church, and were now an hour late for dinner. Relax, the Tylers beseeched us; they'd call ahead. Still, at 8:30 on a Friday night, I thought, parking on Thames Street would be impossible, and our table at the intimate Restaurant Bouchard would probably have found new tenants 45 minutes earlier Then we got our first taste of what makes Newport so appealing at this time of year.

       We turned onto Thames Street to find it empty. In summer, this is a sure sign that a hurricane is about to hit. We parked at the restaurant's front door. Bouchard's, which specializes in elegant, contemporary French food, was nearly empty this off-season evening. When Abby, explaining she doesn't eat sugar, passed on a chocolate soufflé for dessert, our waiter surprised her with an early Christmas gift: Albert Bouchard, the owner and chef, former executive chef at Le Château in South Salem, N.Y., before hanging up his own shingle in Newport in 1995, had time to create a chocolate soufflé for her that was sugar-free. The next morning, a Saturday, we ate pancakes at the Mason House.

       We had planned to head for the White Horse Tavern — first licensed in the 1670's, it's thought to be America's oldest — for a late-morning lecture on the tavern's history and Colonial drinking customs. But the day was so perfectly crisp and sunny and unseasonably warm that we decided to work off our pancakes and soufflés with a stroll on Cliff Walk. We picked an easy stretch of this 3.5-mile shoreline walk — some of it is tough footing over slippery rock — from Forty Steps, once a servants' off-hours gathering spot at the tip of Narragansett Avenue, past the Breakers, Newport's grandest summer cottage, to the tunnel beneath the Chinese Tea House at the back edge of Marble House.

        Both mansions belonged to another famous Newport family, the Vanderbilts. And both were designed by the Beaux-Arts master Richard Morris Hunt. Part of the walk passes through a breathtaking edge of the campus of Salve Regina University, an independent, now coed Roman Catholic institution opened by the Sisters of Mercy as a women's college in 1947. We lingered to admire the administrative building, Ochre Court. This French limestone chateau, the first of Hunt's monumental Beaux-Arts palaces in Newport, began life in the early 1890's as the summer cottage of Ogden Goelet, a New York real estate magnate.

       The afternoon was so nice we also decided to skip the holiday baking class at the Castle Hill Inn and Resort and tours of two mansions, The Elms and Château-sur-Mer — and just keep walking. We began at the Point, the grid of streets between America's Cup Avenue and the harbor just north of the center of town. Dating back to the early 18th century, it is one of Newport's oldest sections, once home to prosperous merchants and sea captains. Carefully restored and scrubbed, the Point is still a real neighborhood. Despite the movie-set look of the Colonial houses and the museum aura radiated by the discreet signs out front detailing the first owners' names and the construction dates, these are private homes.

       The Point is within easy striking distance of the craft shops, souvenir stores, galleries and boutiques of Bowen's and Bannister's Wharf, and we browsed through several. Some clam chowder at the Black Pearl fortified us against the late-afternoon chill. Leaving the wharves, we walked along Spring Street, buying two pairs of wooden hand-carved Noah's Ark bookends for friends at MacDowell Pottery. As the sun set, we returned to our schedule, and headed for the Breakers, one of eight mansions operated by the Preservation Society of Newport County and open to the public (the Astors' Beechwood is privately operated).

       The Breakers is one of three the Society keeps open for the holiday season; the others are William K. Vanderbilt's Marble House and the Elms, built in 1901 for Edward Julius Berwind, a coal baron. Each is elaborately appointed with period ornaments; ornate Christmas trees with fancily wrapped gifts; toy trains; gingerbread houses; poinsettias and other flowers; wreaths, ribbons and garlands; and dining rooms set with period china and silver — exactly as the families might have decorated them. Except, at Christmas, the families wouldn't have been there. And that's the holiday secret that makes the mansions Newport's best Christmas fantasy. Grand as they were, they were just summer getaways. Still, a dose of truth can't dampen what you'll experience within — especially at the Breakers.

       The very symbol of Gilded Age gilt, the four-story Italian Renaissance-style palazzo commissioned by Cornelius Vanderbilt II, the commodore's grandson, has inspired awe since its front gates opened in 1895. I gasp every time I walk through the door, and I do that once a summer. But visiting the Breakers at Christmas was different. The abundance of decorations certainly added to the atmosphere. So did the cellist and the pianist in the Music Room and the hard-working high school choir caroling from the grand staircase in the Great Hall. But the real joy was wandering through the house without being part of a tour.

       The Preservation Society's holiday evenings are in an open-house format. With the four-page brochure handed us as we entered, Abby and I were left gloriously on our own in the most ornate surroundings imaginable. We spent nearly three hours — two more than the tour — taking in the Ren- aissance fireplaces, marble walls, painted ceilings, 12-foot crystal chandeliers, columns and butler's call boxes we'd really just whizzed by before. As the docent on duty in Mr. Vanderbilt's bedroom noticed us ambling through for the third time, he asked if we knew why mirrors surrounded the walls above eye level. I guessed the risqué obvious.

        No, the docent corrected, Mr. Vanderbilt was a gentleman. The mirrors simply enhanced the movement of light around the large room. Yet all the light in the world can't keep the cavernous Breakers from feeling formal and imposing and rather like a stage set. In contrast, our three-hour Sunday lunch at the Astors' Beechwood — which is literally being used as a stage set during the holiday presentation — seemed anything but. We felt like guests rather than tourists. It was Mrs. Astor who initiated what turned into the Gilded Age stampede toward bigger and more impressive real estate when she deemed Newport the place to summer. In 1880, she and her husband bought her 1853 Italianate villa, and Vanderbilts, Belmonts and Goelets soon followed.

        Today Mrs. Astor and her world are memories, but Beechwood tries to give them form through a resident troupe of actors that puts on a spirited re-creation of the Astor household. I found it all more fun than realistic. To be honest, the "living history" notion made Beechwood the one mansion I'd actively avoided, but Christmas curiosity got the better of me. At worst, Abby and I would get to see the place and eat some turkey — at $70 a plate. Of course, there's more to hanging with these Astor stand-ins than eating. On arrival, we informally wandered around the first floor of the house before Mrs. Astor's staff ushered us to tables in the lavish ballroom she added in 1890. Then before dinner, each cast member was assigned a table of guests to escort on a more formal tour. Christmas at Beechwood turned out to be great fun, even if I never did ask the actor playing John Jacob Astor IV about the Titanic.

       The meal, which included apple walnut salad, turkey breast with cranberry cornbread stuffing, and a decidedly anachronistic bread pudding topped with mascarpone caramel sauce, was punctuated by interludes in which the family led us in Victorian- era singing and dancing and toasting. After dinner, a spirited round of carol singing ended with a "Hallelujah" chorus in need of more robust voices than our full bellies could supply. But there was still time — if we hurried — to hear a more formal "Messiah" at Trinity Church. On a late Sunday afternoon in summer the drive from Beechwood could easily take a half-hour, and parking near the church would require a small miracle. We were in our seats in 10 minutes. Hallelujah!