Here at the end of the I-66 asphalt rainbow, Sid Willey has found brass and boat supplies. After 19 years around Philadelphia as a mechanical engineer, Willey, 59, has opened for business on Main Street, hoping to cash in on the bounty that I-66 is bringing over the Blue Ridge Mountains, 90 miles west of Washington.

In the storefront are Royal Brass clocks and knockers and horseheads--"the Old Town touch," he calls it. In back are the beginnings of R and R Products, soon to begin distributing nationwide boat supplies like ladders and brass-inlaid wheels.

In Willey's opinion, Front Royal is ideal. "People want to get the heck away from the city, and this is as good a place to come as any," he said. "And with I-66 you can get out here right quick. We welcome anyone who wants to come live out here--and especially anyone who wants to spend."

Front Royal and Warren County have welcomed many newcomers like Willey in the last 10 years, retirees and couples and families who have come to this lush little valley between the Blue Ridge and Massanutten mountains for rural peace and a country life style.

In the last 10 years, the combined county and city population has grown almost 40 percent, to 21,000. Available housing has increased by 60 percent in the same period and the median value of housing has almost tripled to $40,500--though it is still far below within-the-Beltway suburbs like Fairfax, where the median value of a house is more than $95,000.

Yet, while E.I. Du Pont de Nemours last year opened a $20-million paint plant in the county that employs 250 local residents, and a group of Main Street merchants has raised $20,000 to recreate a Victorian streetscape in hopes of attracting tourists and weekend buyers to the center of town, the growth of business has been somewhat disappointing, according to chamber of commerce spokesman Edwin H. Harper.

"I-66 has been good to us, but if recession wasn't so bad and money wasn't so tight, I know it would have been a lot better. People just don't have the money to spend," he said.

In truth, I-66 has been a mixed blessing so far. While it does afford the Washington suburbs greater access to Front Royal (which likes to call itself "The Gateway to the Blue Ridge Mountains"), it also affords Front Royal residents greater access to Northern Virginia and its shopping malls.

Although county sales of general merchandise--furniture, clothing, appliances and the like--have increased 217 percent in the last 10 years, residents spend only about $930 a person a year at county businesses.

"From the point of view of local government," said R. Edward Duncan, executive director of the Lord Fairfax Planning District Commission, "residential development in the absence of a lot of commercial development does carry some liabilities."

Because a great number of the newcomers are former suburbanites--white-collar workers from Northern Virginia whose high salaries have tipped the scales and caused per capita income to rise almost 100 percent to $10,000 a year--they have brought with them suburban expectations and increased demands on government.

"People come to Front Royal partially because of its low tax rate," which is 60 cents per $100 on real estate, said Front Royal Mayor John Marlow. "Yet they want paved roads and street lamps and round-the-clock police patrols. It's something we have to balance out."

All the same, Front Royal and Warren County have done a good job keeping their books balanced. After taking into account the impact of inflation, the cost of Warren County government has increased only slightly (7.8 percent) in the last eight years. And if lending rates come down, Marlow said, the area has great potential to attract the business and industry that would bring lasting prosperity.

Located near the junction of I-66 and I-81, Front Royal is served by 12 national trucking lines. Freight service is provided daily by both the Norfolk and Western and the Southern railways. There is a small county airport for private aircraft and an electrical generating plant that serves the county.

"We're in good shape right now to handle a considerable amount of growth," said Marlow. "You know, it's a strange thing about growth. In a lot of places, by the time you realize you're growing, you've already grown and by then it's out of hand. But that's not the case here. We're ready for whatever comes."