There it was, at Union Station, all shiny and silvery and serene in the flood of homebound commuters who trampled the red carpets that led to its doors and stared uncomprehendingly at it -- a vision from the past: a luxury train.

At the moment its four cars were bursting with press freeloaders and public relations people drinking champagne (New York) and eating cheese. People who haven't seen the inside of a newspaper in years were bustling up and down the corridors. Some were going on to Atlanta later last night. For a press bash, it was charmingly old-fashioned.

Something called 20th Century Rail Tours is behind it, with American Express handling the marketing. We're talking about a nine-day run from New York to Los Angeles in top-of-the-line Pullman cars dating to the '30s and '40s, classics leased from private firms.

Starting in April, these special trains will travel both east and west, serving no more than 20 couples on a trip, with stopovers in New Orleans and Phoenix.

The cost is terrific: $2,295 per person one-way. But look what you get: nine days of gourmet meals and drinks, live entertainment and dancing, 24-hour room service, first-run movies on closed-circuit TV, fresh linens nightly (with a chocolate on every pillow), limo service to and from all stations and hotels, rooms at the St. Regis in New York, the Beverly Wilshire in L.A., the Arizona Biltmore and so on, manicurist, fresh cut flowers daily in the rooms, corsages, overnight shoeshines and embossed stationery.

When the kids were small, back in the '50s, you would take the California Zephyr over the Rockies to Chicago. Two adjoining roomettes for the five of you. Breakfast in the room with canned peaches. Triscuit and peanut butter lunches. Crumbs on the rug. You took turns going up to the VistaDome where you gawked tirelessly at the sheer black streaming rock faces of the mountains that roared straight up from the tracks to fill the sky. You glimpsed the scrape marks left by Chinese road gangs cutting tunnels through live rock. Once, all peacefully reading and doing puzzles at the picture window, you saw a cowboy lounging on his dusty horse on a dirt road waiting for the train to pass: dingdingdingdingDINGDINGDINGdingdingdingding . . .

"We have the only electric diner in the country here," said Tucker Lamkin, a collegiate-looking vice president of 20th Century Rail Tours. "It has its own generator and can support two other cars. There are 400 to 600 privately owned cars in the country, but hardly 10 percent are useful to us because they have to be electric, among other things."

His firm is negotiating with various corporate owners to line up a pool of private cars for charter trips as well as the regular runs, which will go about every three weeks. Once off the eastern seaboard, with its low tunnels, the trains will add VistaDomes. Huge amounts have already been spent by the owners to doll up the cars with ashwood panels and latticework, elegant furniture and even a piano. 20th Century added another $400,000 in electrical improvements, generators and other invisible details.

"These things cost $300,000 apiece," said Lamkin, "and another $40,000 a year to keep up."

Some of the passengers will have to share a shower, but each person gets a free shower robe. The main sleeping car has 11 compartments with uppers and lowers; another sleeper offers four double bedrooms and 12 crew roomettes. There is a dining-lounge car, a combination bedroom-lounge car and the observation car at the end with six more bedrooms.

The roomettes haven't changed a bit. All those cute little spaces -- the cubbyhole where you put your shoes to be shined in the night, the tiny bathroom, the table that folded down from the wall so you could play go-fish with midget cards, the hideout on top of the closet. Nickel-plated panels with their keys and dials: Air conditioning. Temperature. Fan. Porter. Night light. The first rule was: Nobody calls the porter until we say so. Oh, and the ice-water spigot and the dispenser of cone-shaped paper cups. That didn't last long. But what a thrill. An ice-water spigot right in your own room.

The staff is hand-picked, including young waiters from top restaurants and semi-retired Pullman porters who know how it used to be. The chef is Susan Greenlick, a James Beard prote'ge'. And get this breakfast menu: eggs benedict, roast beef hash, wheat cakes, blueberry pancakes, steak and eggs, French toast, poached eggs with crabmeat and cheese, deviled Virginia ham, bacon and sausage, grits, home fries, cereals, rolls, spoon bread, bran and corn muffins and orange praline toast.

"The transcontinental tours will recreate the leisurely grace and style of an earlier period," says the press release. "Our goal is to provide our passengers with a touch of luxury from a bygone era, a time when private railroad cars were reserved for the elite and privileged."

Leave your Triscuits and peanut butter at home.