We peered into the cave entrance. It was small, no larger than a micro-wave oven. Clad in our polyester garb, helmets, gloves, knee pads and cave essentials, we turned the key and unlocked the gate. The bat-friendly gate was an overly heavy bar that draped across the rectangular tube leading into the cave. Moments later all four of us had shimmied through the mouth of Emerald Cave.

A sliver of sun shot through the entrance, making it hard to see deeper inside. I slid the bar back into place and locked the gate. We all exchanged glances and took deep breaths, ready to explore. Excited to be somewhere new, Steve, in typical style, snorted and said, “Ah, fresh cave!” We crawled through a slot-like tunnel leaving the daylight and the entrance room behind.

We were in search of Emerald Cave’s Yellow Brick Road, a passage that leads to Oz: the city of shields, a giant room dotted with cave shields. An unusual octopus-like formation, shields are rare in most caves but abundant here.

The cave grabbed our attention right away. Fifteen feet from the entrance was a three-story-high hallway. An exposed traverse like a narrow balcony skirted 30 feet above the floor near the top of the ceiling. Our eyes and brains were still adjusting to total darkness as we moved deliberately along the polished traverse. Once across, we traveled through the first few rooms, naming formations and looking behind us. Later, this would help us remember our way out.

The cave was hot, about 70 degrees F, and humid. It had the distinct earthy smell that cavers love. We moved quickly and carefully, yet slowly enough to appreciate the dramatic formations that dripped from the ceiling and coated the walls. They were white in color and sometimes sent sparkles shooting into the darkness. We chided ourselves for not being able to conjure up more intelligent vocabulary to describe the beauty of the features and settled for “cool,” “wow,” and “look!” The words felt basic compared to the complexity of the process that created them.

	Rappelling into the Big Room Pit, a 60-foot descent. © Hampton Uzzelle

We rounded the next corner, took one look, and began uncoiling the rope. To our left was a mud slope that dropped into a seemingly bottomless pit. Ahead, a wet slab of rock disappeared into darkness. Bridget descended the rope, traversed the floor of the pit and climbed out the other side. She fixed the end of her rope, creating a tensioned line over the pit. We put on our harnesses, clipped into the rope and ziplined across the chasm. Safely on the other side, we regrouped, left our rope behind for the return and kept crawling. Staying in the primary passage, we chose to follow the telltale signs of old caver tracks. Hours passed like minutes. We lost any sense of time without clues from the sun.

Finally, Steve suggested a snack break. We looked at our watches. Five hours had passed since the entrance. We ate carefully over our cave bags. Hampton, still curious, looked down the passage behind him while we ate. He gave a yell, testing the size of the echo. We all listened, knowing that a big echo means big cave. “Can you feel air?” Bridget asked.

Echoes and blowing air were enough for us to pack up lunch and keep exploring. Already deep below the surface, we dropped a second rope down the tunnel that Hampton discovered. He descended first, disappearing another 100 feet down. Seconds later, a muffled “off rappel” encouraged the rest of us to follow. Once off rope, we were again traveling through huge rooms. We raced on, spurred by the nervous anticipation of what we might find ahead. We crawled, bouldered, slithered, shimmied, grunted and stemmed our way through the passage. An hour later, we climbed into a gigantic room. The ceiling was 200 feet high and the room seemed as big as Grand Central Station. One look around and we all knew that we had found the Yellow Brick Road—this was Oz!

We lay down on our backs in awed silence. There were dozens of shields dangling from the walls above. The sides were coated with white, sparkling flowstone. Up close, thousands of straw-like calcite needles twisted and gnarled, defying gravity. It was the perfect cave landscape. Hours of exploring would have been worth a moment of this, but we took an hour of moments soaking in every micro feature with our senses, engraving this picture in our minds. And then, it was time to go.

Coming out of a cave is a joyous sensation. As you leave the guts of the earth, the sliver of light at the entrance beckons you back. Being without light gives new value to color, light, contrast, definition and your sense of smell. The outside world seems richer. There is a famous quote about why people climb mountains. In that quote, it describes how getting to the summit of a peak allows you to understand better what is below you and makes you appreciate where you came from. Unlike caves, you can see the mountains without actually visiting or climbing them. So, why go underground? Caving will make you wonder, with every step, what might possibly exist below you. But the catch is that you’ll never know what lies beneath—unless you take the chance to explore one of the wildest places around.

Betsy Treadway, a NOLS instructor since 1998, is a program supervisor at NOLS Southwest in Tucson, Ariz. She also finds time to take NOLS students into the “guts of the earth” on the caving sections of Semesters in the Southwest.