Driving around Cobb from mid-April until the end of June can be a study in ritual. This year, perhaps more than others in recent memory, I've noticed people on sidewalks and quiet neighborhood streets gearing up for The AJC Peachtree Road Race.

You don't have to be clairvoyant to know what these joggers are doing. Most are not wearing old Peachtree T-shirts that might give them away. But, since I'm out jogging year-round myself, I can recognize a practicing runner when I see one.

I can't explain why 50,000 people gather each year near Lenox Square to begin this July Fourth ritual. I've run the race about four times. Thousands of Peachtree runners are year-round exercisers, but many are not. What makes the occasional runner enter the Peachtree?

The Peachtree is an event, a happening, and people gravitate toward major events. Although the Peachtree is exquisitely planned, the race has an air of spontaneity and a feel-good sense of community that folks want to be a part of.

And then there's the T-shirt. Without it, would people come?

I wore a Peachtree T-shirt years ago in the Marine Corps Marathon in Washington and cannot tell you how many times other joggers noticed the shirt and yelled out "Peachtree!" It's just an interesting phenomenon.

A few years later, I was jogging up on Capitol Hill and saw then-congressman and current AJC Opinion columnist Bob Barr walking toward me as I was wearing the Peachtree shirt. He was looking down at the Mall as he approached, distracted by that great vista. "Hello, Congressman Barr," I said. He abruptly turned his head, seemed to instantly recognize the T-shirt, and gave me a hearty hello back.

People don't always run the race either. There's nothing in a rule book that says you can't walk the whole six miles, and thousands do. Some take this as an opportunity to express their individuality. My favorite was a gentleman I passed a few years ago during the race wearing a tux, a top hat and carrying a glass of champagne.

Others line the raceway and encourage the participants with cheers, water and snacks. Still others, much younger and more resilient than I, are on balconies drinking hefty amounts of beer — yes, that early!

The Peachtree is a cavalcade of activity, an Atlanta tradition that kicks off the Fourth of July celebration with a unifying tone and turns this large and diverse city into a community with a small-town feel. And, yes, that T-shirt. It will be worn in numerous venues, almost as proudly displayed as Ol' Glory herself.

Craig Allen of Marietta has lived in Cobb County for eight years.