ROCK STAR ARIZONA'S KARTCHNER CAVERNS AN ODDITY OF GEOLOGIC ACTION.

Byline: ERIC NOLAND Travel Editor

BENSON, Ariz. -- White cones, resembling styrofoam, suspend from the ceiling. Knobby posts appear to have been artfully sculpted with hammer and chisel. A bumpy protrusion is engulfed in shiny goop, as if toffee had been poured over it from a great vat.

``Otherworldly'' doesn't begin to describe the subterranean wonderland that is Kartchner Caverns, in the Arizona desert southeast of Tucson.

Its geologic features are the kind of thing that more commonly spring from the imagination of set designers on futuristic movies.

That might account for the ``oohs'' that routinely emanate from people who take guided tours of these dark bowels of the Whetstone Mountains. It might also explain tour-goers' powerful urge -- strictly forbidden -- to run a hand over some of these bizarre shapes and surfaces.

It was Kartchner Caverns' good fortune to be discovered by two young men with scientific backgrounds. That tempered their wonder with respect for the painstaking processes that formed the cave's oddities over 200,000 years. Just as easily, it could have been stumbled upon by hooligans desirous of bagging a goofy stalagmite for the mantelpiece, or of leaving behind a girlfriend's name etched into centuries-old flowstone ooze.

In a remarkable display of discretion, amateur spelunkers Randy Tufts and Gary Tenen kept their find a secret for years, until they gained assurances that the caverns would be preserved, managed and carefully monitored. They first shimmied into the cave in 1974, then didn't inform the property owners about their find until 1978, didn't bring the state government in on it until 1984, and didn't witness the first public visits to Kartchner Caverns State Park until 1999. (Tufts died in 2002.)

``Sometimes you have to open it to the public to preserve it,'' said Bob Casavant, research and science manager for Arizona State Parks.

The park management of the caves -- and the revenue from more than 1 million visitors who've toured them over the past seven years -- has ensured that souvenir hunters and graffiti vandals are sealed out, and that visitation is closely controlled. The stewardship has also included an ongoing scientific study of the caverns' origins and ecology.

Two tours, each 1 1/2 hours in length and involving about a half-mile of walking, are offered. The Rotunda/Throne Room tour is conducted year-round, while the Big Room is toured only from now through mid-April -- because a community of bats uses it as a maternity nursery in the summer, and park officials don't want to disturb them by trooping tourists through.

In advance of the tours, a comprehensive orientation to what lies beneath can be gained in the Discovery Center. After perusing the exhibits, you might conclude that spelunkers are in a constant state of famishment during their explorations.

Among the names given to various cave formations: popcorn coralloids, fried egg stalagmites, turnip shields, carrots, bacon drapery, butterscotch drapery, moon milk, soda straws.

Also told here is the remarkable story of Tufts and Tenen. In the early '70s, they were students at the University of Arizona in geology and entomology, respectively, and came upon the caverns after Tufts, tramping among these desert hills, discovered a small opening in a sinkhole.

Cave hunting is clearly not for everyone. Tales are told of the two wriggling through a blowhole no bigger than the interior of a coat hanger, and squirming on their bellies along tunnels barely 10 inches high, their nostrils assaulted by the overpowering scent of bat guano.

The visitor's experience is much less arduous today. After Kartchner became a state park in 1988, mining crews carefully cut tunnels into the caverns, and designed them so that stair steps would not be needed; the tour pathways, as a result, are fully wheelchair-accessible.

Because it took humans so long to discover these caves, management of them benefits considerably from hindsight. Carlsbad Caverns in New Mexico suffered after an elevator was installed in 1931; it proved to be a vent for warm, desert air that began to dry out the cave's natural features. Kartchner's interior is protected by two air-lock doors in the entry tunnel -- ``like a meat locker,'' Casavant said as we entered with an afternoon tour.

Because visitors bring in unwanted invaders -- microbes in the lint of their clothing, skin that is constantly scaling -- the tour group is fogged by a misting device at the beginning of the visit, and at the end of each day the walkways are washed down.

It can be a disorienting experience to descend below the earth, even under these carefully controlled conditions. The temperature of the caverns averages 68 degrees year-round, yet the humidity level is that of Florida in summer -- 98 percent.

One ranger recalled a woman visitor who assumed it would be cold in the cave, and wore a sweat suit; she nearly fainted toward the end of the tour.

Also, parents are warned that children age 6 and younger often get uncomfortable in this damp, dimly lit, eerie environment. Within minutes of the start of our tour, a child and parent opted to be escorted out.

Those who remained were continually fascinated. Guide Emily Bennett described the colors of the cave and the substances that account for them: white from calcite, red from iron oxide, black from manganese, tan and brown from silt and clay, yellow from decaying organic matter.

Directing her flashlight beam, she revealed bacon drapery and butterscotch drapery. Also helictites -- curlicues of calcite that twist this way and that, rather than suspending straight down. One ceiling formation resembled a chandelier. Another appeared to be a wavy sheet of white cloth.

Soda straws may be the most remarkable feature of all. These delicate stalactites hang like filaments, and are painstakingly formed by a drop of water repeatedly falling from a spot on the ceiling. It is astounding to think that these formations will grow at a rate of just one-tenth of a millimeter per year. And here is one that is nine feet long.

The caverns are home to another soda straw that is 21 feet, 2 inches long, but the tour walkway goes nowhere near it -- for obvious reasons. ``One sneeze and that would be it,'' Bennett said.

At one point, we were asked to be silent ``and listen to the cave.'' In the stillness, there were only distant dripping sounds, a reminder that Kartchner Caverns is no relic under glass. It's still forming.

That process began eons ago with cataclysmic shifts in the earth that left a block of Escabrosa limestone at the base of a granite mountain range. Subsequent seismic activity created faults and fissures, and natural forces took it from there.

Said Casavant, the cave research manager: ``The (rain)water comes down the hard rock, hits the limestone, infiltrates directly in and dissolves out.'' The result: a 7-acre expanse of exotic caverns.

Water seepage is also responsible for many of Kartchner's elaborate formations, called speleothems. Water picks up minerals on its journey, but when exposed to the air of the cave, the droplets expend their carbon dioxide and can no longer hold their minerals. A tiny deposit forms. Repeat this process continuously for 200,000 years and all manner of oddities take shape.

Human eyes did not behold them until the two explorers aimed their headlamps into the darkness. Scientists who have studied the cave since it became a state park have found no human remains in it. That means that man likely walked on the moon before he set foot in here.

But other creatures found their way in. Among the bones discovered in the caves were those of a 7-foot Shasta ground sloth (which expired 86,000 years ago), a prehistoric horse, a bear and a coyote.

The Throne Room tour concludes at an overlook of Kartchner's most magnificent feature, Kubla Khan, a thick, knobby tower that rises 58 feet from the floor of the Throne Room (which itself is 70 feet high). As tour patrons sit on benches in the dark, lights alternately illuminate different aspects of the tower, and the music of Adiemus plays softly on a sound system.

Kubla Khan was an obvious name after a friend of Tufts and Tenen, taken into their confidence so he could stand watch while they were exploring, christened the caverns Xanadu, after Samuel Taylor Coleridge's 18th-century poem.

The Kartchner name was later settled on because that was the ranching family that owned the land -- and was so receptive to the idea of this treasure being protected as a state park.

Coleridge's opening lyrics are familiar to many a schoolchild: ``In Xanadu did Kubla Khan/ A stately pleasure-dome decree.'' But the applicability doesn't end there. In later stanzas he wrote of ``that deep romantic chasm'' and ``caverns measureless to a man.''

``All who heard,'' he concluded, ``should see them there.''

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IF YOU GO

GETTING THERE: Kartchner Caverns State Park is a 55-mile drive southeast of Tucson, Ariz., near the town of Benson. Take Interstate 10 east to Highway 90 (Exit 302) and head south for nine miles.

HOURS, COSTS: The park is open daily from 7:30 a.m. to 6 p.m. The park entrance fee is $5 per car, but this is waived if you have made advance tour reservations. The charge for the Rotunda/Throne Room tour is $18.95 for adults, $9.95 for kids ages 7 to 13. The Big Room tour resumes today and will be offered through April 15. It costs $22.95 for adults, $12.95 for kids ages 7 to 13. Children under 6 are not allowed on the Big Room tour. Reservations strongly advised for tours: [phone] (daily between 8 a.m. and 5 p.m. local time).

LODGING: Camping is available at the state park for $22 per night; no reservations taken, arrive before 5:30 p.m. There are a number of motels at the interstate exits in Benson.

INFORMATION: azstateparks.com/parks/parkhtml/kartchner.Line is overdrawn html. (Tour reservations may also be made online.)

CAPTION(S):

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Photo:

(1 -- color) no caption (Kartchner Cavers)

(2 -- 4) Above, the Foothills Loop Trails climbs into the Whetstone Mountains near Tucson, Ariz., where the elaborate network of caves known as Kartchner Caverns was formed. Below left, exhibits at the cavers are designed to resemble the cave interior itself. Below right, the boots worn by Gary Tenen and Randy Tufts, who discovered the caverns in 1974.

Eric Noland/Travel Editor

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IF YOU GO (see text)