Moaning Cavern

Moaning Cavern is a solutional cave located in the Calaveras County, California, near Vallecito, California in the heart of the state's Gold Country. It is developed in marble of the Calaveras Formation. It was discovered in modern times by gold miners in 1851, but it has long been known as an interesting geological feature by prehistoric peoples. It gets its name from the moaning sound that echoed out of the cave luring people to the entrance, however expansion of the opening to allow access for the public disrupted the sounds. The portion of the cave developed for tourists consists of a spacious vertical shaft 165 feet tall, which is descended by a combination of stairs and a unique 100-foot-high (30 m) spiral staircase built in the early 1900s. It is open to the public for walking tours, rappelling, and spelunking. Including the off-trail areas, the cave reaches a depth of 410 feet (124 mm

Moaning Cavern is also an archaeological site, where some of the oldest human remains known in America were discovered. According to archaeologist Phil C. Orr, these human deposits were about 12,000 years old, for they were under 420 mm. of speleothem mineral deposits. Nevertheless, there are also many other human bones in these caves, some of them from the more recent periods.

Phil C. Orr also discovered the important Arlington Springs Man remains that are now considered authentic.

There was a lot of controversy about these and other remains in the caves. For example, the Calaveras Skull, found in the same area was deemed to be a hoax.

The cave has long been the resting spot for the bodies of prehistoric people who fell into its opening.

Moaning Cavern is home of the largest single cave chamber in California. The massive room reaches over 180 feet before funneling into smaller passageways. With a 20 30 foot thick ceiling, the open area inside the chamber is, in fact, tall enough to hold the Statue of Liberty (pedestal excluded). There is only one natural entrance into the chamber in the form of a 30-foot vertical chimney dropping into the center of the room. This does make commercial entry a little difficult so dynamite was used in the mid 1800s to expand a natural crack in the ground wide enough for stairs to be built down. The narrow wooden staircase ends at a flat platform 65 feet underground. From there, a ten story spiral staircase leads down to a second platform at the base of the chamber.

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