SLAB CITY, CALIF. - When Charlotte Hagemann, a pumpkin decorator from New Jersey, rumbles into Slab City in her motor home each winter she sets up next to Carl Gross - a sturdy World War II veteran and her high school sweetheart.

For a few months, Ms. Hagemann and Mr. Gross rekindle old ties and even host a St. Valentine's Day party. But as soon as the temperature climbs toward 100, she's gone, leaving her "gentleman friend" to fend for himself.

"I just follow the sun," says Hagemann over sandwiches with friends in her well-appointed motor home whose wheels are covered in canvas skirts. "I don't go nowhere I need winter clothes."

With spouses out of the picture and their children grown, hundreds of senior women are hitting the road for good, leaving retirement communities, shuffleboard tournaments, and the snow far behind.

No one knows how many single women roam the campgrounds, roadsides, and truck stops of North America in motor homes and trailers. But their RVs outnumber those of men at some gathering spots, and their blend of independence and moxie is on display to anyone who bothers to look.

"When people ask me where I live, I say wherever my motor home is parked," says Mary Richardson, a divorced grandmother and winter resident of Slab City.

Yet even though these nomads are loners, they are far from alone. Here in Slab City, a ragtag community of snowbirds near the Arizona border, there are no fewer than four social clubs, including the Wandering Individuals Network or WIN, sometimes referred to by the menfolk as "Women in Need."

RV social networks 

The Traveling Pals singles club charges $15 per winter for a communal P.O. box, and offers afternoon "happy hours" under the shade of a tarp and movie nights featuring DVDs played on a computer monitor. There are plans to dance the night away at coming Slab City "prom." But many women reject any permanent arrangements that might tie them down.

Men "want someone to come home and take care of them," says Jody Schmuki, an energetic former Los Angeles court clerk. "We outlast men, and I think we're really more adventurous than men. The men don't like to travel. The ladies like to go out and see things, even if we won't see our friends for a year."

Women traveling on their own sometimes turn to subterfuge for their own sense of safety. "I've seen very long chains that go out to a large, empty collar and a big bowl of water, implying there's a big dog inside the RV," says Suzi Dow, coauthor of the "US National Forest Service Campground Guide." "And some go to the Salvation Army and get the biggest pair of old work boots and leave them next to the [RV] entrance. The message: The owner of these boots is inside."

But even if women would prefer a partner to fill those boots, older American women must deal with a shortage of available bachelors. The 2000 census reported that among the 65-and-older crowd, there are 70 men for every 100 women. The female-to-male ratio in Slab City is about 3-to-1.

If relationships do develop among RV dwellers, known as "tepee creeping," they tend to last until it's time to pick up stakes and move on, keeping in touch by cellphone and e-mail - or not.

Just keep on moving on 

Hagemann, who decorates and sells pumpkins with paintings of cartoon characters, takes advantage of a national camper service that forwards her mail as she travels among New Jersey, Oregon, California and Florida. Other nomads - "full-timers" in the lingo of the road - will head north to Canada and states like Idaho and Wisconsin, returning south as winter approaches.

While the very nature of nomads make them hard to count, some experts estimate that 500,000 people travel the US without a permanent home, including RVers, fruit pickers, homeless truckers, and train jumpers, says British expatriate Richard Grant, author of a new book, "American Nomads: Travels with Lost Conquistadors, Mountain Men, Cowboys, Indians, Hoboes, Truckers and Bullriders."

Mr. Grant found plenty of seniors on the road. "I grew up in Europe, and old age and retirement is thought of as a settling down, armchair and slippers and your garden, until you stop moving altogether," Grant says. "It was admirable to find a woman of 75 driving from Alaska to Mexico and back every year and managing her own rig."

Some nomads, especially those with $200,000 or $300,000 motor homes, prefer to roam within national networks of comfortable campgrounds that provide services like running water and electricity. And then there are those who visit Slab City.

Home Sweet Slab City 

For more than 20 years, RVers have flocked to the 640-acre abandoned World War II military base east of the Salton Sea that once served as a World War II desert training ground for General Patton. Nothing remains of the base but concrete slabs, an empty swimming pool, and the occasional artillery shell.

Now, in the winter at least, the flat, scrub-filled desert landscape is covered with a crazy quilt of motor homes, trailers, and tents, along with a stage for bands to play on Saturday nights, a portable building that serves as a church, and a makeshift library.

The residents include the rich, the poor and the unusual. There's "Insane Wayne" Smith, who frequently sings at "The Range," Slab City's version of a nightclub. Then there's "Pappy," a caretaker of his own small nudist colony ("though most of the time only Pappy is there," confides one occasional visitor).

Roamers can set up home in Slab City for free, but there are no hookups so the residents - perhaps a thousand in the winter, about 100 in the summer, when the mercury hits 120 degrees - must port their own water and generate their own electricity, which they typically do with solar panels. But everybody looks out for one another.

"When I came here in 1999, it was about 30 minutes before there was a knock on the door and somebody asking, 'Would you like to go for a bike ride?'" recalls Ms. Richardson. She had no bicycle, but the woman at the door, Hagemann, quickly rustled one up.

Life isn't entirely carefree on the slabs. The law comes in occasionally to tow away abandoned cars, clear away piles of junk, and crack down on swap meets and liquor. But even though sheriff's deputies aren't nearby, problems seem to be rare. "We keep a low profile," confides Edith Delaware, while waiting for Slab City's weekly nondenominational Christian church service.

Joys of the open road 

Even were the risks greater, many of the women here wouldn't give up the joys of life on the road. "I'm never lonely," says Hagemann, who spends much of her time chatting with neighbors, running errands on her red moped, and maintaining her RV. "I like to sit down and do puzzles, but I never have time."

Like other nomad women, however, Hagemann hears from relatives who would like to see more of her. Indeed, nomads often leave children and grandchildren behind.

Ms. Schmucki, the former court clerk, says her son in New Mexico used to worry about her, too. But then she started telling her nomad friends to drop by his house. Suddenly, her son had lots of visitors. "He says, 'Mom, you've got a lot of friends. And I don't worry about you anymore.'"