Cavedwelling

Arizona Summer Wildcat CASEY DEXTER/Arizona Summer Wildcat The regular Colossal Cave tour runs several times a day. The more expensive ladder tour is offered only twice a month.

If tight, dark spaces that smell strongly of bat guano seem attractive, Colossal Cave's ladder tour is the perfect summer escape.

About 30 minutes from the University of Arizona campus, Colossal Cave is a cool, if musty, 70 degrees year round.

But claustrophobics beware - the cavernous journey offers close encounters with stalagmites and stalactites, reaching a total depth of six and a half stories down, off the beaten path into passageways rarely seen by others.

The typical tour is an hour-long hike into the paved trails of the cave, but for $35, explorers gain access to areas in the caverns that most regular visitors are not even aware of.

Colossal Cave maintains a temperature of 70 degrees throughout the summer.

Amateur spelunkers are equipped with only a hard-hat and a flashlight to protect against looming ceilings and seven species of bats living within the cave.

The 90-minute tour travels all along the narrow catwalks and foot-wide ladders built by the Civilization Conservation Corps in the 1930s.

The CCC was a federal project that hired men to develop natural resources during the Great Depression.

Joanna Barker, who has been a tour guide of Colossal Cave for about a year, said it was first used by the Hohokam Indian tribe during bad weather conditions because of the cool temperature.

Frank Schmit rediscovered the cave in the 1920s and mined bat excrement - guano, which is high in nitrates, which could be used to make gunpowder.

The tour comes across areas such as the "the living room," where Schmit, who first gave tours of the cave, camped out overnight with his patrons. His underground ventures often lasted for days.

The majority of Colossal Cave has been explored solely by bats, early century outlaws and employees of the park.

Besides historical value, Colossal is full of natural sculptures, chiseled by the centuries-long flow of underground water.

The intricate stalactites and stalagmites were formed from thousands of years of water seeping through the limestone and causing calcite in the rock to crystallize.

But Barker said years of human exploration have led to contamination of the cave.

"Everything we touch won't grow anymore, because the oils (from human skin) won't let the calcite crystallize," she said.

Only 40 percent of Colossal cave is used for guiding tour groups. The majority of the site is left to the resident bat population.

Broken stalactites hang from the ceiling caused by "souvenir vandals" in the 1800s. The walls show drill holes where the CCC placed candleholders.

Old water barrels are still stored in the back crawl spaces from when government officials used the cave as a fallout shelter in the 1960s.

Barker said, however, that the cave was a poor choice for a shelter.

"If a bomb hit this it'd be gone," she said.

While tunneling underground may seem like an extreme way to avoid the desert heat, Colossal Cave offers a shelter from changing seasons, where history is hidden away and time stands still.

For the full experience, the ladder tour takes place twice a month, by reservation only.