To what lengths will they go? How far are people willing to drive for the privilege of working in the metropolitan area while living in more affordable housing in a more rustic setting?

A hundred miles, one developer is betting.

Drive about 100 miles from the District and you could wind up south of Cambridge on the Eastern Shore, or north of York, Pa., or on Town Hill in picturesque Allegany County, what boosters call "the Mountain-Side of Maryland."

So Michael Carnock, principal of PDC Inc. of Columbia, has taken an option to pay $3 million for 935 acres of forested mountain valley land in eastern Allegany County that is two hours and many mountain ridges removed from Washington. He is negotiating to buy 400 acres more to complete the project.

The proposal has been highly controversial in Allegany County, filling the letters columns in the local newspaper and generating 78 exhibits and 25 hours of testimony over seven nights this summer before a county zoning panel.

The location, Carnock said, is about 50 miles from Hagerstown, 70 miles from Frederick and about 90 miles from Gaithersburg and the high-paying, high-employment Interstate 270 corridor. In Carnock's view, it's a no-brainer.

"If I was going to draw a realistic radius, I would think you'd get folks going to Germantown, to northern Montgomery County, to work," he says, standing on the shoulder of Scenic U.S. 40 by the land he hopes to develop. "You can get there in an hour and a half in rush hour."

Carnock's site adjoins 47,000-acre Green Ridge State Forest and is a mile or two from Interstate 68. From there, it's a straight shot to where the jobs are. And, as housing prices closer in soar to ever-higher heights, there appears to be a growing market for this, the newest frontier in the ever-expanding exurbs.

"I think everything's moving this way," said James Stakem, president of the Allegany County Board of Commissioners.

"It wasn't that long ago that people thought it was crazy for folks from the city to move out here and commute back and forth, but that's exactly what happened," said Steve Goodrich, planner for Washington County, which sits immediately east of Allegany County. "Green Ridge might seem a little wacky right now, but in the long run it's believable."

Carnock's proposed project, named Terrapin Run for a stream that goes through it, would bring 4,300 housing units and 11,000 people to a pristine, sparsely settled area of Western Maryland. The eastern end of Allegany County is a land of steep forested ridges, verdant valleys and a mere 2,400 people. The planned community would become the county's second densest concentration of humanity, ahead of Frostburg (7,873 people in 2000) and smaller only than the city of Cumberland, with 21,000 residents.

Terrapin Run, the developer says, will attract, among others, "active adults." He defines this demographic as those 55 and older who will commute for two or three years before retiring, and the recently retired who want to be within two hours of their former homes, children and grandchildren, "so they can watch the grand's soccer game at 3 p.m. and be back here for tee time at 8 a.m."

To serve this population, Carnock proposes building a 23-acre equestrian center, a hiking trail and a shopping center to complement 2,280 single-family homes, 424 townhouses, 912 condominiums and 684 apartments.

He envisions a street with condos above retail shops, "similar to Montgomery County's Kentlands," in the new urbanist style but far away from any existing urb.

Carnock said his company has been involved in developing 1,700 lots in 26 projects. He has built residential subdivisions in Prince George's County and is in the second phase of a 150,000-square-foot commercial project in Stafford County.

Here in the mountains, Carnock is appealing to Allegany County's deep desire for economic growth after decades of high unemployment, job loss and population decline. He promises 20 years of construction with local contractors providing much of the labor. He promises a development that would boost the county's sagging population by 10 percent and, Carnock said, increase its tax base as well.

He hopes to break ground next summer, starting with detached single-family houses and "patio homes" for the "active elderly."

Carnock, a University of Maryland MBA, plans to name streets after members of the Terps' 2002 championship basketball team: Dixon Drive, Williams Way, Blake Court. Given the hurdles and his 20-year time frame, however, there will be no fast break. Terrapin Run could develop at a turtle's pace.

Carnock said it's too early to say how much Terrapin Run units will cost, but sale prices will be guided by "affordability, availability and lifestyle." Allegany County's median home prices are the lowest in Maryland -- $77,138 for first-time buyers and $90,750 for others in April this year. That compares with $344,150 and $405,000 then in Montgomery County, and $255,000 and $300,000 in Frederick County.

Montgomery County Executive Doug Duncan said there are already people commuting to Rockville from Pennsylvania and West Virginia. His brother lives in Boonsboro in Washington County and makes the daily commute to and from his job in Gaithersburg.

Allegany County is a bit far for a regular commute to Montgomery County, though, Duncan said. "If you're working in Frederick, I can see going" to Allegany to live, he said. Nonetheless, he added, it would be better to add jobs in Allegany than to dump more traffic onto already congested roads linking Western Maryland with the rest of the state.

Carnock said he expects to attract the largest number of buyers from Frederick County. "Frederick is becoming a large employment center as firms move north from Rockville and the high-priced Washington suburbs," according to his brochure. "Employees of these firms are finding it more difficult and more expensive to find housing in Frederick or Washington counties."

Allegany County's business and political leaders were quick to back the project. After decades of disappointment -- the completion of the National Freeway and the Rocky Gap Resort and Conference Center both seemed to offer economic salvation for the depressed region, but failed to deliver -- Terrapin Run seemed like the answer to an Appalachian prayer.

"People commuting from the Washington, D.C., area want planned communities like this," Commissioner Barbara Roque told the Cumberland Times-News. "The more people we bring into the county, the more tax base we have to work with."

Barbara Buehl, executive director of the Allegany Chamber of Commerce, sees Terrapin Run as "just an evolution of where our county is going." Buehl herself moved six years ago to Allegany from Howard County, where she commuted to work in the District.

After she moved out, she said, "I actually commuted for a while. I went several times a week. I have to tell you, I didn't feel any more stressed driving from here to D.C. than driving from Howard County to D.C. It may have taken longer, but the last half of it [heading home] is a nice drive."

Despite disagreement over Terrapin Run, there is consensus that a metropolitan market already exists. "Everyone here commutes somewhere," said Dave Reusing, a former builder and developer who moved from Anne Arundel County four years ago to refurbish and run a 1916 inn at the top of Town Hill. "There's no work out here."

Brothers William and Wayne Joy are Allegany County natives who live near Reusing's hotel. To get to their jobs at the State Department, they leave at 4 a.m. They've been doing this for 15 and 20 years, respectively, driving 113 miles and two hours each way. "You go down there for the money," said William Joy, 38.

"If we leave at 4, by the time we get to 270, there's bumper-to-bumper, but it's not stopping all the time. Everybody that lives closer to work tells us we're crazy for making that drive," he said. But, he adds, housing is more costly "down there."

Not surprisingly, opposition has developed to Terrapin Run. Citizens for Smart Growth in Allegany County, whose members include both transplants and natives, has argued that the proposed site lacks necessary infrastructure and that water and sewer problems are insurmountable. "I understand what he's trying to do," Reusing said. "But it's the wrong project in the wrong place at the wrong time."

The county planning board approved the project in June. But critics note that the county's comprehensive plan calls for this area to remain primarily farmland. To proceed, Carnock had to get a special zoning exception from the county board of appeals. This entailed a proceeding of unprecedented length this summer. It is expected to conclude Tuesday night with a final rebuttal from Carnock, closing arguments, open board deliberations and a vote.

As the controversy has flared up, some officials have tempered their early pro-growth rhetoric. "If Terrapin Run meets all standards, I'd be for it," the formerly unequivocal Stakem said in an interview.

Buehl said: "At this stage, there's a difference between the desire and the do-ability. People are concerned -- at least I am -- that everything, like the challenges on the water, the environment, will be taken care of by the process. To say unequivocally we're for it is difficult. But are we for the concept? Do we hope it can happen? Absolutely."

Still, both sides of the debate agree that, as Dave Williams, the developer's local public relations man, put it: "The concentric rings of Maryland's growth from the Beltway have reached our borders."

Or, as Dave Dorsey, the zoning board secretary, whose wife commuted daily for nine months from Cumberland to a job in Falls Church, said: "The middle of nowhere might be moving westward."

Terrapin Run, named for a stream that goes through it, would bring 4,300 homes and 11,000 people to an area of Western Maryland that has 2,400 people, making it the second-most populated area in Allegeny County behind Cumberland.

Demonstrators at Rising Phoenix Retreat Center, near the proposed housing site in Western Maryland, voice opinions on Terrapin Run.

Buttons in support of the proposed Terrapin Run development in Allegany County, which seeks economic growth after decades of unemployment, job loss and declining population. Dave and Donna Reusing own a bed and breakfast on Town Hill. "Everyone here commutes somewhere," he says. "There's no work out here."

Michael Carnock says it is too early to say how much the homes will cost at Terrapin Run, but prices will be guided by "affordability, availability and lifestyle." The developer, a University of Maryland MBA, plans to name streets after members of the Terps' 2002 championship basketball team.