Pg 1, 2, 3, 4, 5, 6, 7, 8, 9

After countless years of slow drip after drip, these rings form a hollow, straw-like cylinder. As the cylinder develops, droplets run down the inside as well as the outside and merge at the tip in a formation with the shape of an icicle, known as a stalactite. A similar process occurs on the floor of the cave. When the water droplet splashes on the floor, carbon dioxide escapes, leaving behind -- because of the splash -- an irregular layer of calcium carbonate, which eventually will grow into rough cylindrical formations. These formations rising from the cave's floor are known as stalagmites. The process of making the cavity itself takes longer than making the formations, and geologists say the interesting thing about a place like Kartchner is that it may not be the final curtain call: Over time there may be changes in the chemistry and the formations, and as a result the formations can keep changing. Kartchner is an almost pristine example of the whole process. Limestone caves are abundant, but, unlike Kartchner, most of them are inaccessible. The vast majority are also extremely small, although there are exceptions such as the chamber at Carlsbad Caverns, New Mexico, which is nearly a mile long and 350 feet high.

Throughout the dizzying network of boulders and narrow passageways in Kartchner, walls are decorated sporadically with an elaborate frieze consisting of curled and calcified limestone helictites, formed by water forcing its way through tiny fissures. Pale draperies or curtains -- formed when trickling water deposits an undulating line of calcite on the underside of a sloping ceiling or wall ---sometimes are striped with alternating layers of reddish brown bands (produced by various iron compounds) that look remarkably like large slabs of bacon. In fact these formations are called "cave bacon," and some spectacular examples can be seen in Kartchner. Other large deposits in the cave appear to be perfect sunny-side-up eggs, although their surfaces are smooth and hard. Like Carlsbad, Kartchner Caverns is home to a population of bats. Between 1,000 and 2,000 insect-eating bats, most of them pregnant females, move into Kartchner's Big Room from May to September and raise their young. You may see or hear small bats in the upper reaches of the subterranean landscape, flitting among thin, coral-colored fingers that hang like drapes behind shallow pools of cool water.

Studies of the bat guano found in the Throne Room -- where bats no longer live -- show that they roosted there some 50,000 years ago.

The bats are an important part of the life cycle of the cave. Their excrement acts as fertilizer, providing nutrients that enable other organisms to grow. These organisms have grown for thousands of years in complete darkness, an important consideration for preserving the cave in its original condition. Park designers, intent on keeping the cave functioning as naturally as possible, chose special lights for the cave that would not encourage the growth of algae or any of the other life forms that might be affected by a change in the light levels. Kartchner is remarkable because it is a "wet" or "live" cave, meaning that the calcite formations are still growing. Though the terrain outside the cave is arid, the cave's relative humidity averages 99 percent all year. And while outside temperatures can reach 100 degrees in the summer, the temperature inside the cave remains right around 67 degrees. To minimize the damaging effects of the dry outside air on the cave formations, air locks have been installed. If the formations lose their moisture, they stop growing.

Text provided by Arizona State Parks

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