Dottie Kerns drove a good 30 miles yesterday from Leesburg to Falls Church, just for a scoop of soft ice cream dipped in nostalgia.

Kerns, 37, is a loyal and longtime customer at the Frozen Dairy Bar, an institution that evokes the past even as it serves the present. It began selling homemade "frozen custard" in Falls Church in 1950, and today, amid fast food chains with mass-produced, air-injected milkshakes, the tradition continues.

"This place is a landmark," Kerns said. "It's one of the constants with everything you see changing around you. I hope it never changes. This is a national institution."

Another customer suggested that the place belongs in the Smithsonian Institution, along with a diner the museum has just acquired for display.

It is not at all imposing. It is a small, squat, white building with reddish trim, topped with a neon ice cream cone, at 6655 Arlington Blvd. (Rte. 50). It is not quite old enough to be Art Deco but interesting enough to have been the subject of a silk-screened poster.

The poster by James Craig English adorns one inside wall, contrasting in its newness with the old Electro-Freeze ice cream machines and the three Fletcher brothers, ranging in age from 43 to 50, who own and operate the place.

Ray and Carl wear caps that say "Howdy! Po' Folks." They bought the dairy bar three years ago from brother Bob, who went to Texas but, with the economy gone sour, returned a month ago to work for them.

The dairy bar was started by brothers Guy and Walter Sponseller, who sold it to nephew-in-law Bob in 1974.

The dairy bar, which serves chocolate and vanilla flavors, is open seven days a week from 1 to 10 p.m. Prices for cones and dishes range from 70 cents to $1.30.

"You get all kinds of customers here," said Ray Fletcher. "Working class people -- carpenters, laborers, general construction people. Also bank executives. One of the Beach Boys was in a couple of weeks ago when they were giving a concert at Wolf Trap. {Fairfax County Board of Supervisors Chairman} Jack Herrity stops in every day to buy ice cream from us."

On a good day, 500 to 550 customers stream through, Fletcher said. Occasionally, a customer such as Buel Lanpher comes along, to spend $17.97 on a bulk purchase, in this case for his daughter's surprise engagement party.

Even on a day like yesterday, with high temperatures only in the low 80s and with low humidity, there were lines, but the wait was not long.

"We drove by at 8 p.m. last night, and the line was around the entire building, so we didn't stop," said Frank French, 46, a customer since his high school days in Arlington who was there yesterday with daughters Fey, 8, and Kit, 6.

Marian Selby, 44, another longtime customer, who lives in Alexandria, was driving by yesterday and, although she already had three quarts in the freezer, stopped for more "since the line wasn't very long."

Walter and Jennifer Argote went to the dairy bar three years ago and, incidentally, found a house nearby. Now, the Argotes, who include Vivian, 9, and Carl Henry, 5, regularly walk there.

Jennifer is English and Walter is from Peru, and as customers they reflect the melting pot that has brewed around the tiny ice cream emporium. Oscar and Peggy Morena, from Guatemala, stop by once a week. Brian Munn, 22, and Hyen Bae, 22, both from Korea, also said they are dairy bar regulars.

Diagonally across Arlington Boulevard and Annandale Road, the old Jefferson movie theater is now Chili's and Baskin-Robbins. The old drugstore is a Korean restaurant. The A&P is a tire store.

But on the southwest corner, nostalgia reigns. Next to the dairy bar, a former post office is the "Now 'n' Then Flea Market." And, unlike many shops that bar food-carrying customers, the flea market has a sign that says, "Ice Cream Welcomed Inside."