"Tom Hillegass has been called the swami of swimming holes. (Seriously. He has.) A man who "swoons" for a swim out in the middle of nowhere, clad or un-. A guru with a gospel. And his holy book? It's his Web site, actually, http://www.swimmingholes.org, with photos, precise Global Positioning System coordinates and directions down to the tenth of a mile to more than 1,000 lush and secluded swimming spots across the United States -- 77 in Virginia.

Click on the map on his Web site, and up pops a forest of blue dots for swimming holes, red dots for hot springs and green dots for what he likes to call "roadside" dips just off the interstate.

For the past 12 years, Hillegass, 65, a retired civil engineer for the Department of Transportation, has been virtually single-handedly spreading the word about swimming holes from his home near Landmark in Alexandria. He has visited many, if not most, and tested the waters himself. He figures he gets into a natural pool at least twice a month during the spring, summer and fall. (The weekend before last, he lazed with his wife and friends in a small, crystal-clear pool in the Shenandoah Valley called Mountain Run. And a few weeks before that, he was out in California "researching" 25 or so in the redwood forest.)

The more he quietly yet persistently publicizes the wonders of swimming in nature, as in the days before the proliferation of baby-blue-bottomed concrete swimming pools, the more people seem to be listening. And remembering. He estimates his site gets 30,000 hits a month.

"We are all missing out," he said. "People should go to swimming holes. They just don't know about them."

That's where Hillegass comes in.

Since the days when Mark Twain swam with his boyhood pals in Bear Creek near Hannibal, Mo., the best swimming holes have been among a community's best-kept secrets, part of the closely guarded lore. But Hillegass, a man of few words, is determined to share the wealth so everyone can experience what he has referred to as "returning to the womb."

"It's really the surroundings," he said. "The water feels good on your skin. It smells good on your skin. I spend most of my time in a swimming hole looking around, at the rocks, the trees, the cliffs. It's all just very beautiful."

This is Tom Hillegass's perfect day: Camping out somewhere far in the country. Taking an afternoon hike of a mile, mile and a half. Finding a great swimming hole by 3 or 4 p.m. and soaking for an hour or so. Returning to the campground for a glass of wine and dinner. "If it's a hot springs, then you can stay in until 9 or 10 at night and go back to your sleeping bag. The warmth stays in your body practically all night. It's a nice experience. Laying in a hot springs under the stars . . . "

Like many boys growing up in the 1950s, Hillegass spent his summers at a little swimming hole near his house in Philadelphia. "There weren't a lot of swimming pools then," he said. "And that was in the polio scare days. My mother would not allow me to go to a swimming pool. But at the creek, the water was moving. So I guess my mother thought that that was all right."

But after he grew up and moved away, he forgot about swimming holes. He married and raised three children. When the kids were little, they joined a swim club just across the street and spent their summers splashing around in the chlorinated pools.

Then the family moved to Oregon for two years, while Hillegass was on a job exchange program between the federal government and the transportation department in Portland. In the verdant Pacific Northwest, Hillegass rediscovered swimming holes and discovered his life's obsession. The Hillegasses swam in the Clackamas River, jumped off rocks into the Sandy River, rafted along the Deschutes River. They soaked in natural hot springs, slid down waterfalls and swung from any rope swing that presented itself.

Hillegass was hooked.

He found many of the best spots by word of mouth. Or after driving around for hours, lost. That's when he got the idea for his Web site. What if, he thought, you could compile this wealth of local knowledge of pristine swimming spots -- including directions -- and let other people in on what he considered among the best-kept secrets in America?

Upon returning to Alexandria, he and his daughter began to build the Web site. He listed the 35 swimming holes he knew. Then he pored through hiking books and began visiting any swimming spot mentioned. That was 12 years ago. Now, Hillegass, his mission and his Web site have been written up in The Washington Post, the New York Times and Time magazine and mentioned on blogs throughout cyberspace. He gets a host of e-mails, tips, updates and advice from fellow swimming hole aficionados every day. A few years ago, he picked up a partner, Dave Hajdasz, who scouts out and reports on swimming holes throughout New England.

It's a journey to swimming hole swamihood he never could have predicted. "When I started, I really didn't know where it was going. My wife, Suzanna, liked the swimming holes when we lived in Oregon. But I don't think she realized it would become as big a hobby as it has. But I am pretty persistent when I get onto something. If I really like something, I stick with it."

Suzanna, a licensed marriage counselor, often accompanies Hillegass on his forays into the wilderness.

"It's not like I have a choice," she said.

Hillegass is picky about the sites he lists. If people e-mail him reports about trash or wild behavior, as has happened with a swimming hole in Morgantown near the University of West Virginia, he takes it off his site. Likewise for swimming holes that end up being on private property. He often gets word from local and state park rangers that no swimming is allowed in a swimming hole he lists. "In that case, I'll remove the swimming hole. But if I was there the weekend before and saw 50 people swimming, I won't remove it, but put the park ranger's whole e-mail right there on the site."

State and local governments can be "paranoid" about getting sued if someone has an accident, he said. And accidents do happen -- witness the page of warnings on Hillegass's Web site, with advice about not diving into a swimming hole headfirst to avoid paralysis or death, and keeping one's head above water in a hot springs so as not to ingest a sometimes fatal amoeba. (The lengthy list of disclaimers and his noncommercial hobby status protect Hillegass from liability, he said.)

"My favorite swimming holes are in national forests or in national parks. Somewhere on federal land," Hillegass said. "The federal government doesn't hassle you. The rangers will often send me corrections to my directions or say, 'Don't send people that way, there's poison ivy over there.' The federal government is not paranoid about the liability."

Hillegass also will not list a site that feels "too local," when the natives make it clear they don't want outsiders. It is true, Hillegass said, that there is often a distinct urban-rural divide at some swimming holes. But nothing a good soak can't rectify. "You can find people in some of these places who haven't taken good care of their teeth for a lot of years," he joked. "But then you start swimming and find out they're really nice people. I got an e-mail from some urban folks who at first felt one spot had a little 'Deliverance-y' feeling. But they ended up having a nice time."

Now, about skinny-dipping.

Hillegass takes care to denote which swimming holes are "clothing optional." Most, he has found, are in New England "for some reason I do not know," he said. "I like to joke that New England summers are so short and New Englanders are so frugal, they don't want to buy a bathing suit."

The nude experience, especially at a hot springs, which is often de rigueur, is very particular. "There's a whole different dynamic going on," he said. "People feel very vulnerable when they're nude. They tend to be very gentle with each other." And swimming sans suit in Virginia? "The only thing around here is to go to some really remote place, where nobody's there," he said. "So nobody cares."

These days, with his three children grown and gone, Hillegass never steps foot in the swimming pool across the street. And instead of slowing down in retirement, he has picked up the electric bass, joined a couple of rock bands and is designing the first Web site to list all of the primo public camping spots across the country.

"I'm the leading edge of the baby boomers. They are not going to take to the rocking chair and sit on the porch. They are going to be looking for challenging hobbies and challenging things to do," he said. "What I like to do -- I like to camp, I like swimming holes, I like to hike, digital photography, keeping up on computer technology. . . . It's an important part of feeling relevant when you're retired: staying engaged, learning, communicating socially with people, feeling like you're making a difference in the world."

Hillegass is preparing for a road trip to Kentucky to visit his wife's family. He's plotting his route around some swimming holes he's been meaning to get to. Just don't ask him which is his favorite. Some secrets, it turns out, are worth keeping to yourself.

"I don't ever tell anybody about my favorite ones," he said. "They're all on the Web site. But because they're among one thousand others, I figure it dilutes the crowd."" (Brigid Schulte, 'Virginia,' The Washington Post, September 4, 2008)