After all the battles, all the changes and all the years, B. Powell and Agnes Harrison still have their view, and it is still breathtaking.

From the back yard of Burr Ridge, their 60-acre estate high atop the Catoctin Ridge, the couple some have dubbed "Mr. and Mrs. Loudoun County" can gaze out at the Potomac River bluffs of Maryland and West Virginia rising on the horizon, and endless miles of rolling, green Virginia countryside. There's not a subdivision, convenience store or traffic jam in sight.

But they're there, all right -- 20 miles off in the suburbs of eastern Loudoun. Inside all those new houses and cars are thousands of people who have never heard of Powell and Agnes Harrison, who don't know that for 40 years the Harrisons have been the county's most prominent civic activists, and who have little sense of the Loudoun traditions and values that for the Harrisons are just shy of a religion.

And that, say the Harrisons, is a downright sorry state of affairs.

"That's the saddest thing of all," said Powell, whose ancestors moved to the county in the 1700s. "The people coming into eastern Loudoun don't have any concept of what the 'old Loudoun' is all about."

"We used to have a group called the Old Leesburg Club," Agnes recalled. "We bury friends all the time."

The old Loudoun was a place of familiar faces and small towns surrounded by unending miles of dairy pasture. For more than 200 years, the county's population hovered around 20,000; since 1960 it has quadrupled.

The careers of Powell and Agnes Harrison -- ages 75 and 69 -- tell the story of that changing county, from the old Loudoun of southern gentility, where things seemed never to move too fast, to the new Loudoun of ambitious commuters who leave their tract homes and town houses at 6 a.m. to arrive at their Tysons Corner offices on time.

For years, both Harrisons have been immersed in an endless stream of civic causes and political battles, many of them aimed at ensuring that at least a piece of the old Loudoun survives -- and that the Virginia countryside they love is not completely lost to the sprawling Washington suburbs they abhor.

Now, in the autumn of their civic careers, this challenge is more daunting than ever. The latest development to alarm the Harrisons isn't miles off in eastern Loudoun, but right next door: Will the view from Burr Ridge still be splendid, they wonder, if a Fairfax County partnership wins approval of its plans to build a resort complex with a golf course and luxury homes?

"It's really an outrageous thing," Powell said of his prospective neighbors. "This group has come in here -- they don't know anything about the county, they just want to make money out of it."

Years of civic activity have involved Powell in groups ranging from the Episcopal Church to the Boy Scouts to the Chamber of Commerce, but his most celebrated legacy is in the area of land use and historic preservation.

He is the founder of the Piedmont Environmental Council, a slow-growth group that exerts heavy influence on development issues in Loudoun and around the state. He is also president of Oatlands Inc., a restored mansion, gardens and horse farm in the county.

"Over the last 25 years, no person in Loudoun County has been more influential on the issue of land use than Powell Harrison," said Arthur W. Arundel, publisher of a newspaper chain that includes the Loudoun Times-Mirror. "And don't forget Agnes."

Agnes is a past president of the Leesburg Garden Club and a founder of Keep Loudoun Beautiful, both of which have a stake in land beautification issues. She helped lobby the county government to institute measures against billboards and litter years before other localities followed suit.

Never one to shy from a skirmish, Agnes has locked horns with political extremist Lyndon H. LaRouche Jr., who has a home just up the road from Burr Ridge. In a pamphlet distributed by LaRouche supporters at churches and other places around the county two years ago, the perennial presidential candidate branded Agnes "part of a highly organized nest of Soviet fellow travelers in the county," who has allied herself with "the international drug lobby."

Responded Agnes: "I don't like the idea of a man living in the county who I consider to be evil."

The Harrisons, with their decades of involvement in Loudoun, are frankly admiring of each other's accomplishments. During a recent interview on their back yard veranda, they good-naturedly badgered each other to recall this or that tale, to take credit for this or that achievement:

"You were an 'activist' before that word ever came along, weren't you, Powell?" Agnes said.

"I guess," muttered her husband.

"You were!" she declared, demanding that Powell tell a story from their early years in Leesburg, when he was running an insurance agency and fighting a successful battle to have the town's downtown area declared a historic district.

In those days, the Harrisons and their set placed a premium on good manners and grace -- qualities sometimes carried to astonishing extremes. Agnes and Powell tell a story -- absolutely true, they say -- of friends in Leesburg who threw a dinner party at which the husband up and dropped dead. Unfazed, the suddenly widowed hostess covered the body with a blanket and insisted that her guests relax and enjoy the rest of the evening.

"Thank goodness we hadn't been invited to that one," Powell said.

The Harrisons today enjoy a life of unstudied elegance, welcoming a visitor to Burr Ridge with a relaxed, cordial style. The property -- a large, white house reached by a wooded, winding driveway -- is plush, certainly, but not ostentatious.

Agnes seems to enjoy fussing about the place. On this day, she was consulting with a worker about how to shape a row of shrubs out back. Burr Ridge has been the Harrisons' home for almost 30 years; before that, they lived near downtown Leesburg, about five miles away.

Their four children are grown now, 12 grandchildren having been added to the brood. Lamentably, the Harrisons say, none is living in Loudoun.

After nearly 50 years of marriage, the Harrisons in conversation are like well-practiced dancers: She finishes his sentences with a kick; he pirouettes off her comments with observations of his own.

Powell has a medium build and a head of well-combed white hair. Agnes is graying, but it is easy to underguess her age: She bounces up with graceful energy to fix tea one minute, then swings effortlessly back into the conversation the next.

The Harrisons remain each other's biggest fans. He met her on a business trip to North Carolina in 1940. "He swept me off my feet," said Agnes.

"She swept me off my feet even faster," gushed Powell.

This could get a little thick, but fortunately the Harrisons aren't above casting some barbs as well. "What an embarrassing statement," tweaked Agnes after Powell confessed that he was born in Maryland, where his mother's doctor lived, so under the strictest definition, he isn't a Loudoun native. "You've totally humiliated him."

For all the remembrances, the Harrisons show no signs of slipping into idle anecdotage. Powell has backed away from some causes, but remains active in several, including the Board of Visitors of Virginia Military Institute, where he graduated in 1933. (Agnes graduated from Hollins College in Roanoke in 1938.) Still close to Loudoun politics, Powell can give detailed explanations of the county planning process, and piercing assessments of local officeholders.

If the Harrisons carry a sense of mission about their political battles and civic crusades, it isn't something they think about much. A sense of community should be a given -- not a great sacrifice, merely routine, they say.

By this standard, then, it's not hypocritical for a couple of extraordinary privilege to look at the world with a measure of despair. In his dimmest view, Powell said, he sometimes sees the changes in Loudoun as a metaphor for society's more general decline. "I tend to be pessimistic," he said. "Damn it, the average American doesn't have the feelings of responsibility he used to."

Powell's rise in Loudoun began in full force after his return from World War II, in which he served as a lieutenant colonel. Through his involvement in Leesburg and Loudoun business and civic affairs, he was introduced to a wide range of important local and state leaders. A Democrat, he managed the local U.S. Senate campaigns of Harry F. Byrd Jr.

Other associations came from Powell's involvement in the Episcopal Church. During the 1950s, he was chief financial officer for the church's National Council; he also served on a church commission formed to search for ways to avoid a crisis stemming from Virginia's troubled race relations, a task he now describes as "the most important thing I ever did."

Powell's contacts proved helpful later in a political battle over the construction of what is now Dulles International Airport, which straddles the Fairfax-Loudoun border. Powell recalled his dismay upon learning that Loudoun residents -- most of whom were none too pleased about the airport in the first place -- wouldn't be able to get to it without first driving 30 miles to Falls Church to pick up the airport access road.

Powell and a group of influential friends lobbied Congress and the state to split the costs of building Rte. 28, now the heart of Dulles' high-technology corridor and one of Northern Virginia's main arteries. Agnes calls her husband "the father of Rte. 28."

Almost overnight, Dulles turned eastern Loudoun from a distant outpost into a place that builders were clamoring to develop. It was out of frustration with the fast pace of the county's growth that the Harrisons and like-minded friends formed the Piedmont Environmental Council in 1975.

The group started when Powell, an unabashed Anglophile, proposed raising the money to take officials from Loudoun and Fauquier counties on a trip to England, where, the Harrisons believe, public officials have done a far better job of controlling suburban sprawl.

Since that trip, the PEC -- which counts some of the region's wealthiest citizens among its members -- has become one of the most important land-use groups along the Virginia piedmont from Loudoun to Charlottesville, many political observers say. It has consistently advocated steps to slow growth or channel it away from the open country and toward cities and towns, and insisted that developers pay a larger share toward building roads, sewers and other public improvements.

While this agenda wins praise from some, it has earned the group its share of controversy and disdain. To its harshest critics, the PEC is an enclave for long-time residents -- many of them extremely wealthy landowners -- to entrench themselves against the imperatives of change. In this view, an outmoded elite is standing selfishly in the way of the ambitions of a new class of developers and suburbanites seeking to bring Loudoun into an exciting new era.

Detractors say the Piedmont group espouses an obstructionist philosophy, using negative rhetoric and tactics in a vain effort to impede the county's inevitable growth or anything else not to its liking. More charitable critics say the land preservationists may be well-intentioned but are blind to the need for economic and cultural progress.

"They want to stop all growth dead," said Supervisor Andrew R. Bird III, an eastern Loudoun Republican, adding that the group has had "a polarizing influence" on relations between the eastern and western ends of the county. Some slow-growth advocates, he said, believe that " 'we're here and let's shut the door on everyone else.' "

The Harrisons chafe at that accusation, saying they have devoted their best efforts to bringing Loudoun residents together, not driving them apart. They lament, however, that their vision of Loudoun may be losing ground to those who don't share it.

"I worry about the future," Agnes said. "Where are the leaders? We need people like Powell who have tried to think ahead for the good of the county, who aren't just in it for themselves."