All over California, you will find unique caves that have been formed over thousands of years as the geography and topography of the state have changed. They come in all different shapes and sizes, each one offering its own unique history and features. But there's no doubt that perhaps the most significant underground cave chamber is where you will find today's Moaning Cavern Adventure Park. Come along as we explore this natural phenomenon in the Golden State.

Located a little over an hour east of Stockton in the town of Vallecito in Northern California, you'll find the Moaning Cavern Adventure Park.

The land on which the park sits is believed to have been originally inhabited by bands of native peoples dating back somewhere between 8,000 and 12,000 years. But it wasn't until the 1840s that the cave was discovered by gold miners who came to the area in search of their fortunes.

The name Moaning Caverns stems from what the miners believed to have been moaning sounds emanating from this underground cave chamber.

It makes sense as the cave, which goes down several hundred feet, is the largest single cave chamber in California. And as we all know, sound truly does carry.

Two different types of tours are offered here. The Spiral Tour takes visitors to a flat platform some 65 feet underground via a walkway and staircase into the cave’s primary chamber.

For those up for more of an adventure, they can scale a scrap metal-built 100-foot tall spiral staircase extending deeper into the cave. With 144 stairs, you’ll spiral around and around (7-½ times to be exact) as you make your descent.

The Expedition Crawling & Spelunking Tour is definitely for the more athletically inclined (and those who are NOT claustrophobic!).

With only a lighted helmet to guide you, you’ll squish, squeeze, belly-crawl, and cram yourself through numerous tight and undeveloped cave areas. Each part of the cave reveals another aspect naturally formed over millions of years.

Just this part is astonishing enough in that the space is tall and wide enough that the Statue of Liberty would completely fit inside! The ceiling of the cave at this point is somewhere between 20 and 30 feet thick! And to make it more exciting (if that’s what you want to call it), these passages have been given funky names like Pancake Squeeze, Godzilla’s Nostril, and the Meat Grinder.

After all that exertion you'll definitely work up a sweat. But don't worry, the cave remains a cool 61 degrees year-round.

How long it takes you or your group to go through definitely depends on individual physical abilities and the number of people. But the proprietors advise that you plan on about half a day for this tour.

Back in the day, the miners used candles and whale oil lamps to see where they were going.

Today you and your family and friends can explore in relative "comfort" - if that's what you want to call it! For those with mobility issues or who are just too squeamish to go underground, moaning caves offers an array of family-friendly above-ground activities as well including axe throwing, panning for gemstones, and shopping for souvenirs in their gift shop.

Definitely not for the faint of heart but a wild adventure if you're up for it, Moaning Caverns Adventure Park it's one of the most unusual adventures in Northern California.

Have you been to Moaning Caverns Adventure Park? If so, we’d love to see your photos and hear about your experience there. You can also find out more on their Facebook page.

If you’re looking for other fun Northern California adventures, you might want to embark upon a fun and scenic ride on the Niles Canyon Railway.