It is not a historical site, though some would argue it should be. There are no landmarks, or waterslides for that matter.

Nonetheless, as many as a hundred tour buses from as far away as Florida converge there daily, bringing in some of the 250,000 people who flock to this oasis every week.

Their destination is Potomac Mills, 1.25 million square feet of consumer bargains displayed in a warehouse-like setting with minimal architectural distractions. This sprawling shopper's paradise just off I-95 is the only reference point many Washington area residents have for Prince William County.

And because the prices are right -- many products are as much as 50 percent less than what conventional department and retail stores charge -- some patrons go to extreme lengths to get to Potomac Mills.

Becky Williams, for example, drove three hours in a blizzard from Roanoke Rapids, N.C., on Veterans Day. "I spent $100 in the first 10 minutes," she said happily.

Since the mall opened a little more than two years ago, about 25 million people have visited its 180-plus stores, making it the most popular attraction in Virginia, surpassing even Colonial Williamsburg.

"We try to make the mall a tourist attraction," said Sherry Lewis, marketing director for Western Development Corp., the mall's builder and operator. It is one of the few shopping centers in the country to have a full-time tour bus director, who travels the country promoting excursions to Potomac Mills, Lewis said.

With such marketing tactics, the mall has generated $200 million in sales this year, exceeding expectations, she said.

The mall will get a further boost when Bantam Books releases the next edition of "Born to Shop," a listing of shopping malls nationwide. The pick for best shopping center in the United States? Potomac Mills.

"This mall is probably in the forefront of commercial shopping centers," Lewis said, noting that similar malls are being planned for Philadelphia and Fort Lauderdale, Fla.

Keeping exterior frills to a minimum and concentrating on interior improvements have kept Potomac Mills' overhead costs low, Lewis said. "The rent is about 50 percent of what you would be charged at a traditional mall."

That has translated into deals for bargain hunters, one of the main reasons shoppers travel great distances to get to Potomac Mills, according to a study this year by Stillerman and Jones, an Indianapolis firm that does marketing surveys of shopping malls.

The study said the typical Potomac Mills shopper is a woman, between 20 and 44, whose household income is $45,000.

But more important to the mall's owners, the survey found that shoppers spend twice as much and stay twice as long at Potomac Mills as they do at conventional malls.

The mall's success has been a boon to Prince William, drawing business that shied away in the past, according to John Gessaman, county director of economic development.

The mall has added 3,000 jobs in the county and this year will turn over about $2 million in local sales taxes. In addition, the county benefits from real estate tax revenue and a share of the approximately $9 million in state sales taxes the mall generates annually.

But the mall's success has had a price, too, as traffic has clogged nearby arteries. Local developers are considering forming a special transportation taxing district to build a parkway south of the mall that would cut down on the number of intersections and give motorists unimpeded access to I-95.

Oblivious to such local concerns, Californian Charlie Sickler, 67, and his wife enjoyed their visit to the mall one recent day, stopping occasionally to rest.

"It's amazing," said Sickler, who was armed with a 35mm camera. "Are we near the end yet?" he asked as he approached Neighborhood 5, one area of the mall.

There were still four "neighborhoods" to go -- the mall stretches for more than a half mile -- but nobody had the heart to tell him.