The dancers in the TV spot promoting Washington as a capital city might look more at home in a Dr. Pepper commercial, but the rowhouses and market in the background are authentically Washington. The ad was shot on Capitol Hill, probably the most appropriate community to represent Washington.

Springing up just beyond the front steps of the Capitol, no other neighborhood can call the Folger its local theater, the Library of Congress its neighborhood library or the Capitol its front door. But there's life among the monuments -- just walk a little deeper into Capitol Hill and you'll encounter wide boulevards and narrow streets, Victorian rowhouses skirted by wrought-iron fences, red-brick sidewalks, cicadas, deep shade and the lemony scent of magnolias.

Saturday is probably the best day to visit Capitol Hill -- that's when EASTERN MARKET comes alive. Farmers back their trucks up to the corrugated-steel-roofed arcade to sell an overflow of locally grown produce, newly laid eggs and home-baked goodies. Craftsmen, along with "junque" sellers, set up tables to display their wares. A one-man band may be performing beside the sculpture of the skateboard rider at the north end of the market or a pick-up jazz trio may be in session. Inside the 1871 red-brick market building, there's a perpetual line in front of the MARKET LUNCH CARRY-OUT, open 7:30 to 2:30 Tuesday to Friday, to 3 on Saturday, as the cognoscenti queue up for breakfast or, later in the day, for the crabcake sandwiches that warranted a visit from The New York Times' food critic. Hill residents form a passing parade of market-goers in search of blackberries and corn, families taking kids to swimming lessons at the natatorium around the corner and singles walking their dogs or jogging past. Politicians frequently work the crowd -- recently it was mayoral candidate Patricia Harris. On a fair day, the atmosphere stops just short of carnival.

A walking tour of Capitol Hill is best accomplished in the morning -- come early and have breakfast. Take Metro's Blue or Orange line to the Eastern Market stop, where the nearly vertical escalators will deposit you at the intersection of Seventh Street and Pennsylvania Avenue SE. Cross Seventh and head west on Pennsylvania toward the Capitol.

Walking on the south side of the street -- the same side as the Metro stop -- you'll soon come to the red-and-white-awninged ICE CREAM LOBBY at 615 Pennsylvania Avenue, open Saturday 11:30 to 11:30 and Sunday 12 to 10:30. If you're following the early-morning schedule, it's too early for ice cream, but make a note to come back. I guarantee that their Frusen Gladje Swiss Chocolate Almond is the best ice cream you've ever had, anywhere, any time. Next door at the WINE AND CHEESE SHOP, Saturday 10 to 7 and Sunday 12 to 5, you can replenish your supply of Jelly Bellys or buy a liter of the house olive oil.

In the 300 block of Pennsylvania Avenue, you'll pass the HAWK'N'DOVE and DUDDINGTON'S, favorite watering holes of congressional staffers. Across Third Street you'll come to a little shop that provides Capitol Hill with some of its finest window shopping. MAMORI, Saturday 11 to 6 and Sunday "by whim," sells lusciously exotic hand-crafted women's clothing and accessories, some expensive and all unique. And -- at last! -- at 215 Pennsylvania is the CHESAPEAKE BAGEL BAKERY, Saturday 7 to 7 and Sunday 7 to 3, and because you've waited so long for breakfast, treat yourself to an onion, a garlic, a pumpernickel and a sesame bagel, all freshly baked on the premises.

Continue toward the Capitol on Pennsylvania Avenue, which becomes Independence at Second Street. Turn right on First Street, and pull up short in front of the magnificent NEPTUNE FOUNTAIN at the foot of the Library of Congress. Created by Hinton Perry, it'll make you feel cool on even the hottest Washington day. Behind it, the THOMAS JEFFERSON BUILDING of the Library of Congress, open Saturday and Sunday from 8:30 to 6, is a spectacular example of Italian Renaissance architecture and one of the most beautiful buildings in Washington. (There's wheelchair access on the ground floor.) Inside are two exhibits: "A Nation of Readers," a collection of American reading material including vintage Classic comic books and early paperback novels, and "Fine Prints: Recent Acquisitions," 60 prints demonstrating printmaking techniques from early English to modern American samples. But any show would be eclipsed by the building itself. If you're lucky, the main reading room will be open -- take the elevator up to the gallery to view it. There's a gift shop on the ground floor and, nearby, a film about the library that's shown every hour at a quarter to.

Continue down First Street and cross over to the entrance of THE CAPITOL, open Saturday and Sunday from 9 to 4:30. Take a minute to admire this handsome symbol of our country and then tackle the stairs. (For wheelchair access, ask the guards to direct you to ground-floor entrances and elevators). The best way to see the Capitol is to attach yourself to a tour -- they leave from the Rotunda every five minutes from 9 to 3:45 and include Statuary Hall, the original Supreme Court, the old Senate chamber, the Rotunda and the gallery of either the House or the Senate. Kids love the underground train connecting the Capitol with House and Senate office buildings -- you can ride it Saturday mornings from 9 to 12.

Back outside, it's worth a trip around the Capitol to the west side to look at the grounds and the glorious view up the Mall from the west terrace. You might want to take a short trip down the hill to visit the BOTANIC GARDEN, open daily 9 to 9, 9 to 5 in winter, on the House side of the Capitol at First Street and Maryland Avenue SW. It's a large hothouse containing an indoor jungle and a permanent collection of exotic orchids, along with seasonal floral displays.

Now retrace your steps to the east side of the Capitol and back to the intersection of First Street SE and East Capitol Street. Heading east on East Capitol Street away from the Capitol, you'll walk between the Library of Congress and the SUPREME COURT, open 9 to 4:30 weekdays but not, unfortunately, on weekends. All you can do on a Saturday is admire the building's classic lines and wonder if what you've read can be true.

Next stop: the FOLGER SHAKESPEARE LIBRARY, Saturday and Sunday 10 to 4, at Second and East Capitol streets SE. A gift to the country from Mr. and Mrs. Henry Clay Folger, the library houses their extraordinary collection of Shakespeareana, the world's finest. The Great Hall and the theater are open to view, and below the theater is a gallery with pottery on display. In the gift shop you can buy a T-shirt emblazoned with the much-quoted line from "King Henry VI, Part II": "The first thing we do, let's kill all the lawyers." On some Saturdays, the theater gives a matinee -- "The Merchant of Venice" is its current offering.

Continuing east on East Capitol Street, turn left on Third Street and then right on A Street NE for a one-block detour that will take you to the MUSEUM OF AFRICAN ART at 316 A Street NE, open from 10 to 5 Saturday and Sunday. Housed in what was once the Frederick Douglass home, the museum is now showing carvings, masks and artifacts in an exhibit titled "Thinking With Animals." Adjacent to the museum is what may be the brightest star in the Smithsonian constellation of gift shops: Look for batik, rattan, carved figures, gourds and jewelry in profusion.

Return to East Capitol Street via Fourth Street and keep going east, away from the Capitol. This stretch of EAST CAPITOL STREET is among the grandest and most beautiful sections of the Hill. The street is unusually wide because it was intended to convey inaugural processions from the Capitol to Lincoln Park. In the early 1800s it was used as an equestrian race course by the local gentry. Turn right on Seventh Street SE. The houses become somewhate smaller here, but they're an eclectic mixture of architectural styles: Federal, Classic Revival, 1920s and Victorian, with some innovative renovation thrown in.

When you cross North Carolina Avenue you'll find yourself in the midst of the hustle and bustle and color and noise of Eastern Market, and you're on your own for the next two blocks -- you can't go wrong wherever you turn. If you're ready for lunch, try a crabcake sandwich and unpeeled French fries -- on a mild day, you can take your lunch outside to eat at one of the umbrella-topped tables set up along the arcade. Or, for a great sub, cross Seventh Street to PREGO, Saturday 7 to 7 and Sunday 8 to 5. Inside Eastern Market are vendors of high-quality produce, meat and fish. Breakfast meats are a specialty here -- home- cured, lean bacon with or without the rind and bins of fresh sausage meat spiced to suit your taste. Across the street from the market are small specialty shops owned in large part by Hill residents. Libby Sangster undoubtedly will be sitting outside her shop, ANTIQUES ON THE HILL, Saturday 10 to 5:30 and Sunday 1 to 5. She can tell you more about Capitol Hill than you ever thought you wanted to know.

One more block down Seventh Street, past second-hand clothes shops, antique stores and front-yard flea markets, and you're back at the Metro stop. You've covered two to four miles, sampled the best of Capitol Hill and are probably taking home some souvenirs. GETTING A GUIDE For more information, BRICK WALKS AND IRON FENCES, a walking tour of Capitol Hill by Hill resident Nancy Metzger, is available for $1.75 at Kramer Books, Fourth and Pennsylvania SE. Also, the Smithsonian Resident Associates program sponsors WALKING TOURS of Capitol Hill by restoration expert Ruth Ann Overbeck. Call 357-2700 for details..