GOLD COUNTRY:
California Caverns, Cave City
Black Chasm Cavern near Volcano
Mercer Caverns near Murphys
Moaning Caverns, Vallecito  
Call 866-762-2837 to make reservations with Sierra Nevada Recreation Corp. or see: caverntours.com

SEQUOIA NATIONAL PARK:
Crystal Cave Sequoia National Park $16 approx.
The Cave is 50 degrees inside. A jacket is recommended.
Tickets can only be purchased at the Foothills or Lodgepole Visitor Center. explorecrystalcave.com

SHASTA LAKE:
Shasta Caverns, Lakehead. Getting to the cavern requires a boat ride, then a bus ride for entry. It's included in 1 price, approx. $25.   lakeshastacaverns.com, 1-800-795-2283

MOJAVE:
Mitchell Caverns at Providence Mountains State Recreation  may be closed. Check for details before going, parks.ca.gov for current status

How do you rank on the adventure scale? Are you are willing to squeeze through a "womb" made of rock, climb through tight holes in the earth and wade through goo that's knee deep? Many have backed down or completely freaked out when put to the claustrophobia test at California Cavern, a state historic landmark where tours began in 1850.

Navigating the Womb Room!

Concessionaire Sierra Nevada Recreation Corp. leads trips through three caves and an underground gold mine, providing exciting adventures in the Sierra Nevada foothills not far from Calaveras Big Trees. But before you go, there's something you should know: Are your afraid of enclosed spaces, climbing down stairs and back up again, and having to bend in tight quarters not high enough for standing upright? Also, are you overweight, out of shape, wheelchair bound or afraid of being trapped? If so, don't go!

The tours of Black Chasm Cavern, California Cavern, Gold Cliff Mine and Moaning Cavern aren't designed to be scary but they could turn out that way if you're claustrophobic–and that's just on the mild-mannered walking tours! Adventuresome types can up the ante by taking Mammoth Cave Expedition and Middle Earth Expedition where cavers must negotiate the Womb Room.

Shown in the photo is Middle Earth Expedition, which involves:

• 2.5 t0 4 hours exploring 80% of the cavern system from the east entrance to the western exit.
• Stamina is required on the mile-long adventure.
• Hour 1 includes walking, crawling and squeezing through the historic Mammoth Cave.
• Pass through the Middle Earth mostly walking through knee deep, sticky cave clay–high top shoes a must!
• Explore horizontal fissures in Cave of the Quills.
• Take a quick, 70′ rafting trip across Tom's Lake.
• Navigate passages filled with goo.
• See beautiful crystalline rooms.
• Ascend ladders.
• Step into sunshine and showers.