Exploring Calaveras County caves keeps you cool, puts your imagination in high gear

Oak trees and vineyards dot the rolling hills of Calaveras County, tucked away between Yosemite National Park and Lake Tahoe, a place with four distinct seasons that lend themselves to hiking among giant sequoias, leaf peeping, snow play and, of course, the spring frog-jumping contests that put the county on the map.

The visual bounty above ground is matched by what’s underground, where a different world awaits: Steep staircases lead to narrow passageways and chambers filled with stalagmites (rising from the floor of the cave) and stalactites (hanging from the ceiling).

(Lou Spirito For The Times)

These limestone and marble caves, formed millions of years ago, are worth visiting year-round but especially during the hot summer, when temperatures in these caves don’t generally get warmer than 61 degrees.

Since last fall, my family and I have visited the three Calaveras County caves that are open to the public: Moaning Caverns in Vallecito, Mercer Caverns in nearby Murphys and California Cavern in slightly more remote Mountain Ranch, all within about 80 miles of Yosemite National Park. Each offers 45-minute walking tours led by friendly guides who give geology lessons peppered with corny jokes. And each offers a fascinating look below the ground we walk.

Moaning Caverns

We started our journey at Moaning Caverns, which hold a chamber so large it could fit the Statue of Liberty (minus its pedestal) inside. (For those keeping track, that’s more than 150 feet, about 14 stories.)

Gold miners discovered the cave in 1851. It’s named for the moaning sound that echoes from its depths, which you can hear when it’s very quiet.

In the 1920s, visitors would be sent down into the cave inside of a bucket with only a candle for light, said Joan Wilson, our tour guide.

“They would charge you a nickel to go down and a quarter to come back up,” she said with a laugh.

After learning some of the cave’s history, our group headed single-file down the wooden stairs, taking care to duck the formation known as the “noggin knocker.”

Once we were together as a group on a platform at the bottom of the stairs, Wilson pointed out the roots of a giant oak tree above us, the tree we had just walked alongside before entering the cave.

Wilson answered some questions and posed one of her own. “Do you like rock music?” she asked before tapping a calcite formation that made a hollow thud.

We then descended a 10-story spiral staircase made with materials recycled from a World War I battleship. The staircase’s 144 steps are enclosed in a cagelike structure spanning the height of the massive cavern that provided a sense of security as we made our way down.

At a second platform at the base of the chamber, Wilson pointed out various formations: Screaming Skull, Angel Wings, the Chocolate Waterfall.

A highlight, or ultra-low-light, occurred when the lights were turned off and we were enveloped in complete darkness.

Info: Moaning Caverns, 5350 Moaning Cave Road, Vallecito; (209) 736-2708, moaningcaverns.com. Daily walking tours, known as the Spiral tour, start at 9 a.m. Walking tours cost $20 for those 12 and older, $15 for those 6-11; those 5 and younger are admitted free.

Mercer Caverns

After our visit to Moaning Caverns, we stopped in Murphys for wood-fired pizza and tacos at Firewood, topping it all off with handcrafted ice cream next door at JoMa’s. We then relaxed in Murphys Community Park, complete with an old-fashioned gazebo and a creek.

Mercer Caverns is less than two miles from bustling Main Street, which is full of boutique shops and wine tasting rooms. We’ve done a fair amount of wine tasting here, but on this day, we were all about the coolness of the caves.

Among those who came to seek their fortunes in the California Gold Rush was Walter J. Mercer, who discovered the caverns Sept. 1, 1885; public tours started less than two weeks later. The first visitors toured the caverns using ropes and ladders and holding in their teeth a board with candles. Thankfully, today’s tours have a few modern touches, including walkways, stairs and electric lighting. The tour includes 440 steps — 208 down and 232 up (because you go up a different way than you went down).

We saw formations that resembled a Shih Tzu, a jellyfish and a mermaid. Mercer is also home to delicate frostlike crystals known as aragonite flos ferri (iron flowers).

We again experienced the cave by candlelight and then total darkness.

It was tight quarters on the climb back up the steep staircase. I recommend sturdier footwear than, say, Crocs — not that I was wearing those.

Info: Mercer Caverns, 1665 Sheep Ranch Road, Murphys; (209) 728-2101, mercercaverns.net. (Note that GPS sometimes misleads; go west on Main Street and look for Sheep Ranch Road, a right turn that can be hard to spot.) Open daily; first tour departs about 9:30 a.m. Tours cost $18 for those 13 and older and $10 for children 3-12.

California Cavern

California Cavern is about a 40-minute drive from Murphys but worth the trek. It has been hosting visitors since the early 1850s.

Some of those visitors included naturalist John Muir and writer Mark Twain, author of “The Celebrated Jumping Frog of Calaveras County,” the impetus for the jumping-frog contests each May in Angels Camp.

The cave was an essential part of an old Gold Rush camp called Cave City. Weddings, church services, some court trials and parties replete with music and dancing once took place inside the cave.

Our tour began by wandering through a marble passageway into Council Chambers, where you still can see some signatures from the 1800s. Putting your mark on the walls used to be common — the cave has thousands of signatures — but it is no longer allowed so as to protect the cave, which is now a state historic landmark.

Our tour guide encouraged us to use our imagination as we came upon different figures in the cavern. One large stalagmite in Bishop’s Palace, where church sermons once were given, reminded our 3-year-old son of a giant bear, but others saw Jabba the Hutt from “Star Wars.”

In the Cathedral Room, “cave bacon” hangs from the ceiling and is illuminated from behind. This calcite formation looks like strips of the favorite breakfast meat.

California Cavern offers two cave walking tours depending on the time of year: the Trail of Lights Tour in summer and fall and the Trail of Lakes Tour in the winter and spring.

We had to skip some parts of the cave when we visited in late May, including areas known as the Bridal Chamber, Bed of Nails and the Jungle Room, because they were still underwater after the winter’s heavy rains. But in exchange, we got to see crystalline formations reflected in the pools of water below.

Info: California Cavern, 9565 Cave City Road, Mountain Ranch; (209) 754-1850, cavetouring.com. Opens 10 a.m. daily, with tours on the hour. Walking tours cost $16 for adults and $8.50 for children ages 6-12. (Prices are expected to increase as water recedes and more of the cave becomes available for tours.)