The background hum of morning rush hour traffic dimmed as the foursome walked deeper into the lush, green course. Soon, the prevailing sound was the soft whoosh-thump of a golf club sending a white ball sailing over the fairways.

At 7:30 a.m., while the rest of the world was heading for work, the four men basked in the natural beauty of Fairfax County's nine-hole Jefferson District Golf Course. The early outing is a ritual for them, a constitutional that is loved for the challenge as well as the companionship.

"This is the best sport there is," said Frank Hirt of Arlington. "It's full of exercise, a lot of company, you're out of mischief and out in the air."

Teammate Ernie Roderick of Falls Church agreed. "We like it here. It's not too crowded and you can walk the course for exercise," he said.

Jefferson, a gently rolling course off Lee Highway in Falls Church, is one of four county-run public golf courses. A fifth -- Pinecrest Golf Course, with nine holes -- will open Sunday in Annandale.

The group members strode along the still-dewy fairway, fanning out after stray shots throughout the brisk, breezy morning. The quiet was interrupted by the crack of golf balls, the rustle of trees, the occasional squeak of hand-pulled golf carts, and by friendly chatter.

"I donated a ball to the water," said Mike Finn, who joins the group when visiting his son in Annandale. Finn, who has homes in Texas and Rhode Island, said that while he's in Rhode Island, "I'm a beach bum. In Texas, I'm a snowbird. Here, I'm a hacker."

"I know every blade of grass, every ditch on this course," said John Berglund of Falls Church, who has "been living on a golf course" since he began caddying at 13 in his home state of Minnesota.

"This is my life," said Hirt, who relished a birdie on one hole. Hirt, a widower who looks forward to the regular game for camaraderie, also benefited from having the greatest handicap of the crew, based on being the senior team member at age 85.

A "mulligan," or penalty-free second chance at hitting the ball, was regular fare in this game, since the purpose was enjoyment with only a hint of healthy competition. "We play informal," explained Roderick. "We don't worry about the rules."

Khaki work pants and plain shirts stood in for flashy sports attire. Clubs and bags were admittedly garage-sale gems rather than pro models.

The foursome plays together "off and on," the golfers said, depending on who can make it on a given morning. But most of them show up at least three mornings a week, the earlier the better. They hail from different states, but all worked in government, either federal or local, before retiring. Despite that common interest, politics is rarely a topic for conversation on the links: "We don't let it interfere with our golf, no matter what the world events are," Roderick said.

"The idea is to get out early and have a new awakening," added Roderick, who was quick to recall his teen-age years caddying for champion Francis Ouimet and a later stint as captain of his college golf team. "You get on the golf course and you forget all your problems," he continued. "We're enjoying our last few years together."

By 10 a.m., they had finished their round and were relaxing in the clubhouse. Another golfer, Jim Beard, stopped by for coffee and said he planned to return the next day for his usual pick-up game.

"I could come over any day and go out with people I know and have played with before. Very seldom do you play with strangers," Beard said.

Meanwhile, 90-year-old Reese Metcalfe of Arlington was lining up for his tee-off outside. Metcalfe said he walks the course three or four times a week because "I need the exercise, I like the challenge and the people out here are good company."

Because the course became more crowded during the brilliant spring day, golfer Doramy Poulous of Arlington and her partner, Jennye Marshall of Burke, were still waiting to start their game after an hour had passed. A beginner, Poulous said she is determined. "I'm going to get a birdie if it kills me," she said.

Between 250 and 300 golfers make the rounds each day at Jefferson District Golf Course during the warm weather months, according to Chris Thayer, assistant manager of the course. About 60 percent on any given day are, like the Roderick-Berglund-Hirt-Finn foursome, "regulars" who know each other and come at least twice a week, Thayer said. And, unlike golfers at many courses, almost everyone at Jefferson walks because of the comfortable terrain.

The Jefferson District Golf Course is open from 6 a.m. until dark. The other Fairfax County public courses are Greendale (18-hole par four) in Alexandria, open from 6 a.m. until dark; Burke Lake (18-hole par three) in Fairfax Station, 6 a.m.-dark; Twin Lakes (18-hole par four) in Clifton, 6 a.m.-dark, and Pinecrest in Annandale, 6 a.m.-dark beginning Sunday.

Course fees range from $2.50 weekdays for golfers under 18 to a $6 flat fee on weekends.