B&O RAILROAD STATION MUSEUM -- is open Wednesday through Saturday, 11 to 4, and Sunday, noon to 5. Admission is $1.25; for children 5 to 12, it's 75 cents; FOR MORE ON ELLICOTT CITY -- a brochure called "Chart Your Own Walking Tour of Ellicott City" is available by writing to the Office of Industrial Development, 3450 Court House Drive, Ellicott City 21043; phone 301/992-2344. (They also schedule group walking tours.) Shopkeepers often have the brochure as well.

Sometimes on a rainy evening a train pauses by the old B&O railroad station at the foot of Main Street in Ellicott City, Maryland. The headlamps flicker in the fog, but the station is empty. The last time passenger trains stopped here was in 1949. But it was the first terminus of the first railroad in America.

Ellicott City is more than a forgotten depot: It's been a mill town almost continuously since it was founded by Quaker brothers, the Ellicotts, in 1772. It's a town of contrasts: around the corner from the train station, the now-modern milling operation towers over the crumbling house built for George Ellicott in 1789, its only visible occupants now the grackles gazing from second-story windows.

Ellicott City draws visitors who like the feel of stepping back in time -- here the old opera house where John Wilkes Booth reportedly made his debut, there the cemetery where Ellicotts have been buried since 1795, the l840 courthouse, the 1790 country store, all within a few blocks. And in recent years, many shops have cropped up in the granite buildings that seem to crowd toward narrow Main Street and downhill like a great gray rockslide.

At the foot of this hill, in the Patapsco River Vavlley, is the railroad station, the town's main attraction. It was built around 1831. The first train trip from Baltimore to Ellicott's Mills, as it was known then, had taken place the previous August, when the Tom Thumb, the famous iron horse, raced a real horse and lost.

Inside the oldest remaining railroad building in America, the original waiting room is on the second story -- on a level with the tracks. Old-timey top hats and bonnets hang on imaginary hooks, and cockroaches scale the walls -- painted there in the 1950s, for the occasion of a formal dance. In the turn-of-the-century ticket office, the guide, Herb Johl, showed off his pride and joy, an 1896 typewriter with two complete sets of keys: one for upper case, the other for lower. A wall is covered with tickets and programs and pictures from the Fair of the Iron Horse, held in 1927 to commemorate a century of railroading, and Johl was also delighted to report, "A man was here today who'd been there."

In the part of the building called the car house, an overhead funnel used to vent the steam from boilers on engines like the Tom Thumb. "That's 1830s soot up there," said Johl. The tracks rest on the original beams.

In the 1885 freight house, there's a slide show on early railroading and a chance to admire thw ork of the Mount Claire division of the National Model Railroad Association: an H-O layout of the 13-mile stretch between Ellicott City and Baltimore in the late 19th century. "Talk about detail!" exclaimed a 14-year-old boy as he spotted two small gravediggers suspended in the act of shoveling in a cemetery of tiny headstones in "Baltimore." The viaducts, the valleys, the hotels, the horse-drawn carts, the working streetlamps, the trains coming round the bend -- it was a delight.

Outside, visitors hopped aboard a 1927 restored caboose, a present from the Chessie system. "That's the only thing they've given us," said Johl.

Between the 1831 depot and the 1885 freight house is a turntable pit from the 1850s or 1860s which was partially uncovered by an archeological dig in 1974.

"People come out here and ask, how did these work together? Well," said Johl, "they never did."

We left the station as light fell. An old kerosene lamp was burning in one of the rooms, where the station master might've slept or taken a break. The stairs groaned, the doors creaked as they closed behind us, leaving us in this room. "There's somebody in that bed!" said the teenager with a sense of dramatic timing. We stood and stared at the cot, where we could just see the hair on the top of the mannequin's head under the old brown blanket. We stared at him quite a while, to see that he didn't move, commanding him immobile with our eyes, then looked back again a few times before we left. Late-afternoon light in Ellicott City does such things. SHOPPING -- On Main Street the old railroad hotel is now a gift shop heavy on babies, including the one nestled in the shopkeeper's lap who greets the customers with a friendly grunt, and a kitchenware store. Outside, overhead on a pole at Main and Maryland, is the high-water mark from the flooding caused by hurricane Agnes in 1972. Other nearby stores sell brass and antiques -- an Indian boar-hunting set catches the eye -- health food, and women's clothing noteworthy for its seemingly permanent state of being on sale.

The signs to the shops are obscure, if there are any signs. Deeds Book Shop can be spoted by the paperbacks (a quarter apiece) piled outside the door. Rarer volumes at reasonable prices cram the shelves inside. Most of them are between $2 and $20, with the occasional $100 item, such as an Arthur Rackham-illustrated book of fairy tales. Owner Jean Mattern remembers when she was a social worker about 15 years ago doing case work in nearby dwellings: "I never would've thought then that I'd be running a little bookstore here now." It's not yet much of a tourist town, at least to Mattern. Most of the out-of-towners who stop in her shop are book dealers. To this tourist, a poetry anthology for $1.75 proved irresistible.

Outside, a passerby pointed out the high-water mark to his companion. "Hey, they musta raised it. It used to be lower than that," he observed.

Up the street at Ellicott's Country Store, Enalee Bounds and her mother, Mildred Werner, were astir over two 19th-century Chinese vases that had come in; they would be adding them to the antiques on the three floors above. The ground floor is a cornucopia of things one loves to find in country stores: penny cndy, hand-dipped candles, ribbons and potholders and pots and china cups and dried flowers.

Across the street is Stillridge Herb Shop, a potpourri of sachet pillows, jars of powders and crumbly leaves and cloth bags of sweet and pungent smells. Most of the herbs are grown locally, at the store's own Stillridge Herb Farm in Woodstock. Cinnamon and rose petals, sage and peppermint, musky lavender -- the fragrance of the store is palpable, and its aur surrounds you as you leave and head up the street.

Next is Leidig's Bakery, and brownies: "I'll give them to you for a dollar," said the woman in baker white as she dropped six small brownies into the white paper bag. "They're just ends." It was their unfortunate fate to have come from the edge of the pan, but they were still very good.

Up the street and across from the public library (which used to be the firehouse) is a collectibles shop called simply "Antiques." It's full of wondrous junk -- a Davy Crockett coonskin cap (tail in good condition), baseball cards, tiny crates of Coca-Cola, a carrier pigeon carrier, a German naval commander's leather jacket, a "portable last rites kit" ($35).

Tiber Creek runs through the town: some of the old houses straddle it. This is particularly noticeable near Tongue Row, a bank of townhouses built by the widow Ann Tongue in the 1840s. In Tongue Row there are craft shops --leather, handworked silver, metal sculpture, Indian souvenirs. SNACKING -- The name Cacao Lane sounds like a torch singer, but actually it's one of the nicest restaurant in Ellicott City, and a favorite evening spot for people who come over from Columbia, a few miles away. You enter through the bar, and cross through an alley to the dining room in the building next-door. There, old stone walls contrast with exposed beams and Tiffany lamps of more recent vintage. There's live music upstairs Friday and Saturday nights, 9 to 1. Lunch, which is served 'til 10 at night in the bar includes sandwiches, the quiche of the day, a "French hamburger," sauteed, topped with cheese and then baked in French bread. For dinner, it's continental cuisine, tender veal or sweet scallops, shrimp scampi, steak and chicken dishes. If you're strolling around on Sunday and want to stay for dinner, note that most of the shops close at 5, and Cacao Lane doesn't start serving dinner until 6. They're closed Mondays. By the way, the locals pronounce it "coco lane."

For grabbing a quick bite or a cup of coffee, there's Baxter's, where sandwiches and salads are about $2, or even less. A vegetarian sndwich for $1.75 was two kinds of cheese melted on the freshest rye with lettuce, tomato, hot peppers, onions and herb dressing, and served warm. Besides being inexpensive, Baxter's is quaint, with wooden ceiling fans and red-and-white check oilcloth on the tables and walls lined with sketches and photographs by local artists, whose main theme is Howard County. It's open daily 11 to 6; Monday hours, 11 to 5.