Moaning Cavern– A Pile of Bones, and a Journey to the Center of the Earth.



Calaveras is Spanish for skull.

Sometime in the blustery Calaveras County winter of 1921, Vallecito resident Addison Carley discovered a large hole on a flat near his home. He heaved several rocks into the opening, hoping to gauge the depth, and was answered with silence. Native Americans had been aware of the cavity for years, ostensibly using it as a burial ground. Addison became more than just curious, and as his obsession with the black void deepened, he set out to discover just how deep this hole bored into the earth, and what was in it.

The first records of the existence of the cave date back to 1851, as mineralogist John Trask was contracted by the state of California to survey portions of the Mother Lode Region. Trask was lowered to shallow depths of the cave, but failed to find the bottom, or determine just how large the chamber was.

To facilitate access to the cave, an intricate wench system was designed, as gold miners smelled a potential honey-hole. The miners squeezed into wine barrels secured by rope and were lowered deep into the dark abyss. The apparently large and bottomless cavern was mined for approximately two years, but gold was never found. Gold thrives in quartz veins, but all the miners could find was limestone. As far as the candle would allow the explorer to see, the interior of the cavern was filled with monstrous calcite formations.

Exploration of the cave ceased, although its legend continued to grow. Over the next fifty years there is no record of anyone entering or exploring the cave, but a number of ideas about the nature of the opening were entertained. Rumors circulated of two French explorers seen removing two very old human skeletons from the cavern. Locals developed two theories: the cavern was a bottomless pit, or an entrance to the center of the earth.

Residents were fascinated with the idea of the cave, yet frightened by the possibility that something very real, or even supernatural could live inside. It wasn’t just the unknown depth of the hole that sparked the locals’ curiosity, there was also the unsettling observation that the cave made a very ominous, very pronounced moan.

On Christmas day in 1921, Addison Carley, Clarence Eltrigham, and Dan Malatesta set out to disprove the bottomless pit theory, and succeeded. With 300 feet of manilla rope, they finally hit what they thought was the bottom. Carley had since purchased the land that contained the cave, firm in his resolve to find something — natural or otherworldly — deep inside his investment.

Carly had an additional entrance to the cave blown open with dynamite to enable easier access. Exploration would soon begin, poisonous gases and unearthly monsters be damned.

At around 165 feet, at what Carly had assumed was the bottom of the cave, he made a macabre discovery beyond the small platform where he stood: A huge pile of animal and human bones, calcified over time, in front of a small clearing that contained another large chamber.

It was soon discovered that this additional chamber plunged more than 100 feet underground, though one could only journey down safely to about 70 feet before running out of air. But for now, Addison Carley and his crew had to contend with a huge pyramid of the dead.

Some of the remains were initially removed, but the county soon declared the cavern an ancient burial ground. Removing human remains from a burial site without written permission from the next of kin was against the law. One skull in particular was carbon dated and determined to be over 12,000 years old. The possibility of the cavern being a burial site was obvious, as was the possibility that hapless and perhaps intoxicated explorers fell in and plummeted to a sure and harrowing death.


Them Bones. Photo by William Duke


Photo by William Duke

Addison Carley saw the potential that his hole in the earth could be a lucrative enterprise. He began lowering tourists and adventurous locals down the hole in a halved wine barrel for 10 cents, with the catch being that it would set them back another 25 cents to get back up. Deterred by the liability of this treacherous system, Carley decided there had to be a safer way to get folks to the bottom of the cave. Enter Albert Tangemann.

Albert Tangemann was the owner of Stockton Welding Works. In 1922, he devised a blueprint for a large spiral staircase that would allow easier access to the bottom of the cave. Using scrap metal left over from World War II battle ships, Albert arc welded a 100-foot spiral staircase, a first of its kind.


Photo by William Duke

Moaning Cavern was open for business in 1922, and has remained open ever since.

The twisting staircase was astounding, and for a time was as much of an attraction as the cave itself. However, a unique problem presented itself after construction of the staircase was completed — the cave stopped moaning. What had once been a sinister moan that lured the unsuspecting explorer to the mouth of the cave was gone.

Scientists proposed the moan that bellowed from the entrance of the cavern was a result of the reverberation of the sound of water from a well inside the cave hitting limestone. Over many years this caused the beautiful calcite formations, which populate the inside of the cave. Apparently, the new staircase absorbed the sound, which caused most, if not all of the moaning to cease.

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Calcite Igloo Creature. Photo by William Duke


In 1973, the Potter-Herman Broadcasting Company purchased the cavern and the surrounding property from the Addison Carley estate.

Today, Moaning Cavern is part of the Cave and Mine Adventures, which includes nearby Black Chasm Cavern, and California Cavern. All have guided tours, but Moaning Cavern is by far the largest and most interesting of the three. The sheer size of the cave is so overwhelmingly large, the Statue of Liberty can apparently fit inside the main chamber. To truly appreciate the enormity and beauty of Moaning Cavern, one must stand deep inside the cave and look up at the daylight beaming in from the terrestrial entrance. If you’re lucky, you’ll get to see a fellow explorer vigilantly rappel down from the mouth of the cave and meet you on the first platform.

Outside the cavern, zip lining is available, as is a man-made rock-climbing tower.

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Zip Line. Photo by William Duke

Visitors who desire a longer, more involved tour that doesn’t involve rappelling can opt for the 3-hour adventure trip, which takes you farther into the labyrinth of tunnels inside the cave.

Moaning Cavern is a fun, fascinating excursion. The summer months can be sweltering in Calaveras County, but the average temperature inside the cavern is a cool 60 degrees. Picnic tables are also available outside, so if the weather is agreeable, pack a lunch.