KARTCHNER CAVERNS STATE PARK - The stone is bathed in soft light. The ceiling and walls are shaped in ripples and waves, the colors changing until the light fades away to darkness, to places never seen by tourists.
A couple of scientists and one of the men who discovered the cave lead a gaggle of reporters along well-lit trails, talking about the cave's geology, hydrology, biology and balancing the needs of visitors and researchers. Most of their focus is where the light shines - on stalactites, stalagmites, patches of tiny red fingers of stone that look like horns on small, white stags. But they point into the dark corners occasionally, because much of the cave's value lies there.
Beyond the paved trails, beyond the grand features, lie dark, damp places where people don't go and lights don't shine. About 60 percent of the cave is never seen by visitors. Even the researchers who study the cave rarely enter remote corners.
It has been a little over a decade since Kartchner Caverns became a state park, and scientists are still enthusiastic about its value to researchers, said Robert Casavant, research and science manager for Arizona State Parks.
Unspoiled caves are laboratories for the study of aquifers and geology. The darkness holds a ferment of bacteria, slime, minerals, water and bat guano, so much life that Casavant wonders if a cure for cancer might lie within the cave's juices.
"The nice thing about caves is that they are a three-dimensional window into the near surface" of the planet, Casavant said.
Many caves are destroyed after they are discovered. Serious cavers can be a tight-lipped, conservation-minded bunch, going to great lengths to protect caves. But once word gets out, people without proper training or perspective show up, and the stalactites, stalagmites and other formations, which can take thousands of years to form, are broken, the bats are slain or chased away and graffiti covers the walls.
Kartchner is different because it remains mostly unspoiled, even though it draws 160,000 visitors each year. Air-tight doors seal off entrances. Lights go off after visitors leave an area. Researchers monitor temperature and moisture content. An entire section of the cave system known as the Big Room is turned over to migrating bats in the summer.
The cave system was discovered in 1974 by Gary Tenen and Randy Tufts, University of Arizona students who spent their weekends underground.
"Randy and I were cave hunters. We had found a lot of holes, and none of them went anywhere," Tenen said.
One day they were walking the east flank of the Whetstone Mountains, a ragged sky-island range overlooking the San Pedro Valley. Tufts had found a crack there while hiking with a high-school girlfriend. At the time, he wrote it off as a dead end, but when he returned with Tenen, things were different.
This time, the smell of bat guano and moisture lifted out of the sinkhole, Tenen said. The cave breathed, which is something caves do every few days. Something was down there.
They squeezed through a crack and made their way inside, and it didn't take them long to realize that the cave was large, the cave was beautiful, the cave had to be kept secret.
"We had seen so many caves that had been trashed in Arizona," Tenen said. "We knew that it couldn't last forever because if we discovered it, somebody else could."
They spent a couple of years exploring the cave, crawling through the limestone crack on weekends, finding passages of stalactites; stalagmites; long soda straws; small, delicate formations; a room about 400 feet long by 240 feet wide; the fossilized bones of a sloth that came to rest on the floor of the cave about 80,000 years ago.
They called the cave Xanadu.
When Tenen and Tufts learned that Xanadu was on private land, they set out to learn something about the landowners, the Kartchners, a ranching family in Benson.
When they found out that James Kartchner believed in environmental protection, they took a chance. They showed him the cave, and he went in with them, slithering in the mud. He was "tough as nails," Tenen said. "He and his family were the most honorable people I've ever come across."
Talks began with the state, and a long construction project began. The work, mostly done by hand, went so slowly that the Legislature threatened at one point to pull funding if it wasn't finished quickly.
Today, Kartchner Caverns earns about $2.8 million a year and is one of the state's most-visited parks.
As visitors come and go, scientists study the cave's properties, both living and non-living.
"It's a way to find new life," Casavant said. Samples of bacteria, slime and fungus are carted off and the DNA is sequenced. This information is used to make medicines and other useful products, he said.
Caves also teach us a great deal about water resources and aquifers.
Biologists are learning more about the Cave myotis bats that spend their summers in the Big Room, Casavant said. Researchers are also reviewing insect populations within the cave.
Tenen and Casavant expressed concerns over the cave's future as the state wrestles with budget difficulties.
The fact that Kartchner is profitable is a mixed blessing, Tenen said. "My concern is that there will be a move to turn the management over to a private concessionaire in order to make more money."
Casavant shared this concern.
"What usually suffers are the critters, large and small, that don't have a voice," Casavant said. "The purpose of the park isn't to make money. The purpose of a park is to preserve a resource."
No proposals to turn the park over to private hands are on the table, and Casavant thinks the cave is safe. For now. But other Arizona state parks have been closed or are operating on reduced hours, and the state's debt is a deep, dark hole itself. Even rumors of cuts make Casavant and Tenen nervous.
Tenen hopes that people who visit Kartchner Caverns will become concerned with its preservation - each visitor is someone potentially interested in the cave's fate.
He recalled his first trips to the cave, looking at rock formations thousands of years old.
"Then suddenly you realize you're not alone, 'cause that's bat guano," he said, pointing.
"Every place you look, there's new beauty. One of the wonderful things about caving for me is that sense of wonder. It's a very humbling experience."
Reach the reporter at 602-444-4847.
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