Just as traditional outdoors enthusiasts enjoy mountaineering or hiking, and tech-minded gadget lovers enjoy geocaching, ghost towners have their own agenda: seeking out, documenting and photographing towns that one day will cease to exist.

"We are a subset of the outdoors culture," said Clint Thomsen, of Stansbury Park, who writes newspaper columns about the ghost towns he visits. "If you¹re willing to drive around 200 miles along dirt roads and find something that¹s definitely crumbled, you¹re definitely part of the breed."

Ghost towns are prevalent in the West with 100 to more than 200 per state, but even states in the Midwest and several Eastern states have between 10 and 100 ghost towns apiece, said Todd Underwood of Prescott, Ariz., who hosts a Web site for ghost towners, www.ghosttowns.com.

Underwood, a chemistry professor turned pilot who estimates he has visited a thousand ghost towns, said the site has helped coalesce ghost towners into a group that logs millions of Web site visits a month.

And for those who think ghost towning is only a Western phenomenon, ghost towners are quick to say that even New York has 14 ghost towns. Pennsylvania has what one ghost towner calls a ghost highway, a 13-mile stretch of Pennsylvania Turnpike complete with overpasses and tunnels near Breezewood that was bypassed in 1968.

A ghost town is a place that is a shadow of its past glory. This can include everything from accessible historical towns - like Jerome, Ariz., or Calico, Calif. - to the ruins of forgotten mining towns, abandoned farm settlements or railroad stops that disappeared when the trains stopped coming. Towns that are remote, hard to gain access to and have very little remaining are known as ''true ghosts,'' Underwood said.

Underwood said he began ghost towning in 1976 with his father.

''We were really fascinated as to how and why people would just up and leave towns. We were steeped in the mystery of that,'' he said.

A typical ghost town visit usually begins with an offhand remark from an old-timer or a mention on a Web site, ghost towners say.

Before leaving home, they try to solve the mystery of why the town disappeared and, more important, how to get there by hitting the history books and topographical maps.

David Pike, who grew up in southern New Mexico and now lives in Washington, D.C., has rated nearly 20 New Mexico ghost towns on his Web site.

He says ghost towning has helped him understand how his environment affects him and taught him to live in the moment.

''It's hard to ignore a metaphor when you're standing right in the middle of it,'' he said. ''When you're standing in a building that was once something and now is slowly fading into not being anything anymore, that's a stark reminder about appreciating what you've got when you've got it.''

Laura Aden, who explores old mining sites with her husband mainly in Arizona's Tonto National Forest, says ghost towners are ''the people who walk around with their heads down scratching the dirt, the crazy bunch of people who pick up nails and cans.''

Getting started with ghost towning

Lake Valley, N.M. » The old mining town has several standing buildings, including a schoolhouse, general store and small church.

Frisco, Utah » The old silver-mining town has several outdoor charcoal ovens, a cemetery and standing structures.

Spring Canyon, Utah » The canyon is home to several small ghost towns, abandoned mining camps and a ghost known as the ''White Lady of Latuda."

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