Dark. Cold. Complete and utter disorientation.

I was loving it.

About halfway through a boat tour of Penn's Cave, a natural cavern in central Pennsylvania, guide James Madonna turned off the spotlight he'd been using to illuminate our space. I sat in the inky blackness, unable to make out even the cool and clammy hand in front of my face.

The earth's natural refrigeration generally keeps the temperature in these underground chambers in the 50s year-round. Penn's Cave, about 14 miles east of the town of State College and one of a handful of caves that you can ride through in a boat, has been offering tours since 1885 -- long before the advent of modern climate control.

A few minutes before the tour began, I descended the 48 steps to the mouth of the cavern. As the air turned crisp at the bottom, I slipped on my windbreaker, already questioning the wisdom of wearing shorts. I envied some of the warmer-dressed guests, until I realized that the whole point of this expedition was to cool down and let the 52-degree chill of the cave permeate my bones.

Marketing director Terri Schleiden later told me that Penn's Cave guides are issued uniforms that include a long-sleeved pullover and a jacket, although some of them conduct six or seven tours a day in short sleeves. Employees don't necessarily recommend that visitors be that brave.

"The hooded sweat shirts are a best seller here," Schleiden said.

About 20 of us teetered into the long, narrow motorized boat that James would maneuver through the cavern for the 50-minute tour. As we distributed ourselves between two benches, the flat-bottom boat bobbed back and forth, unnerving a few of the passengers.

Only after we'd started the ride did James tell us that the water temperature is a downright frigid 38 degrees. Thankfully, the only victims to take the polar bear plunge are assorted electronic items belonging to clumsy visitors. By way of comfort, though, James cheekily reassured us that if we fell in, all we had to do was stand up. It turns out that the water is only 3 to 5 feet deep.

As we glided into the cavern, the sparse sunlight illuminated the wispy clouds our breath was forming. I tightened my jacket against the damp and covered my legs with my messenger bag. It's not a bad idea to cover your camera, too: More than a few water drops hit me from above (this, according to James, is good luck).

To start, James regaled us with some of the cavern's impressive facts and figures. About 11 million gallons of spring-fed water pulse through it every day. The limestone that comprises the geological formation is about 500 million years old, while the cave itself is younger, only about 30 million years old.

Native Americans had been visiting -- and even living in -- Penn's Cave before a pastor by the name of James Martin "discovered" it in 1795. With the cave entrance quickly shrinking from view, it wasn't hard to imagine what those early explorers must have felt.

This being the 21st century, however, we had a few modern conveniences helping us in our journey, namely an engine and electric lights. James expertly navigated the cavern's many turns, positioning himself to lean over and flip switches to illuminate its several rooms, including one lit in a series of changing colors.

He used a spotlight that he could detach from the front of the boat to point out noteworthy stalagmites and stalactites. It felt like a Rorschach test. That one, with a resemblance to the Abominable Snowman? OK, maybe. But that other one, supposed to be the pope? Not seeing it. Still, the crowd oohed and aahed at the wonders that nature had wrought, at a rate of about an inch every 300 to 500 years.

At the end of the cavern, we exited onto Lake Nitanee and into a blast of warmer air. After a few minutes of looking for animals (there's also a wildlife park on-site), we turned back toward the cavern. Even before we entered, I could feel the cool air emanating from the opening, creating a wind tunnel as we forged ahead.


If you go:

*Where to stay: Reynolds Mansion, 101 W. Linn St., Bellefonte (800-899-3929; Large B&B in an 1885 house in a scenic town. Rates from $135.

*Where to eat: Pizza Mia, North Spring St., Bellefonte; (814) 355-3738; Daily lunch special: two one-topping slices and fountain drink, $4.99.

*What to do: Penn's Cave, 222 Penns Cave Road, Centre Hall (814-364-1664;; hourly tours year-round; hours vary. Tickets, $16.50; seniors, $15.50; children 2-12, $8.75.