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• Out of the forest and into the frying pan
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• The quiet side of the Dells
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• Sightseeing on the St. Croix
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• On the rocks in the Ozarks
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• Spring in the Baraboo Hills
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• Wisconsin's Icelandic outpost
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• Drama on the Prairie Coteau
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• Land of big water
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• Isle Royale reverie
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• House in a park
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• Hitting the trails in Trempealeau
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• Devil's heaven
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• Afoot in the Porkies
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• A present to the future
  Love the land? Then help preserve it for the next generation.

Cave country

In southeast Minnesota, scratch the surface for a glimpse of splendor.

Under the cornstalks of Fillmore County, an unusual sculpture garden sits in shadow.

Stalagmite topiaries line walkways, alongside pale-green flowstone as translucent as Chinese jade. Stalactite statuettes dangle in artistic arrays.

They’re obviously created by a Pollock of rock, a Van Gogh of stone. Yet their genius relies not on the medium — water, applied one drop at a time — but on eons worth of time.

A billion years ago, the floor of this underground garden was the silty muck on the bottom of a tropical sea, encrusted with the shells of mollusks. Over time, it compressed into porous limestone, cut through by underground streams.

Rain, acid and gases ate cavities in the stone, and the streams carved twisting labyrinths, picking up minerals that colored the walls — manganese for purple and brown, iron oxide for red and orange, calcite for white and yellow.

Rivulets laden with these minerals dripped into the cavities, spreading tapestries of flowstone along the walls, glistening stalactites overhead and nubby stalagmites on the ground. They’re still growing, as are the chalk-white soda straws — baby stalactites, lengthening by an inch a century — that carpet ceilings.

Niagara Cave was discovered in 1924, when three pigs disappeared from a farm near Harmony. The farmer, looking for his missing pigs, found a sinkhole — a spot where the thin layer of limestone under the soil has collapsed — and sent some neighbor boys down by rope.

Seventy-five feet later, they found the pigs — still alive — and a huge labyrinth of underground canyons. Tours began in 1934 and still start from the pigs’ landing spot, the Reception Room.

Mystery Cave was discovered on a frigid day in 1937, by a man walking along the South Branch of the Root River. Because the air inside the cave is 48 degrees Fahrenheit year-round, it had melted the snow on the ground around a sinkhole, and steam was rising from it. He found a whole system of caverns, and tours of Mystery Cave, now part of a Forestville/Mystery Cave State Park, started 10 years later.

In summer, a visit to these underground caverns is a good way to beat the heat, since the air always is a bracing 48 degrees. The cold also is responsible for Fillmore County’s status as a trout-fishing mecca; water that takes a short cut through the caves rejoins the South Branch of the Root River chilled to 48 degrees, allowing trout to thrive.

“If it weren’t for the caves, you’d have to pack up and go to Montana to find trout,’’ says Chris Ingebretsen, a DNR naturalist who begins his tours by showing visitors the nearly dry bed of the South Branch as it skirts the caves.

The surrounding countryside, he said, looks ordinary, even bucolic. But appearances are deceiving.

“It’s karst topography, which means there’s fractured limestone right under the surface, and water drops down into the fractures and disappears,’’ he said. “It’s odd country — there’s not a lot of solid ground in Fillmore County.’’

Ingebretsen was leading a tour of Minnesota Caverns, also known as Mystery 2; there’s also a Mystery 3, he said, along the 13-mile system. Most people who go on the Mystery 2 tour, held only on summer weekends, already know something about caves, and my group was handy with answers — “What forms stalagmites?’’ “Water dripping off stalactites!’’ and “How do bats navigate?’’ “Echo location!’’

He described the sculpting powers of water, aided by carbonic acid, also used in soda pop — “Most people don’t give a lot of thought to the fact they’re drinking something that makes rock dissolve’’ — and led us through triangular rooms.

On the walls, fossilized worm burrows created a Swiss cheese effect. Pure-white helictites twisted and curled, and a beautiful, pale-orange carrot stalactite (think “c,’’ for “ceiling’’) reached toward the floor. One pale-green, translucent stalagmite (think “g,’’ for ground’’) looked just like the Minneapolis Institute of Art’s famous “Jade Mountain.’’

At the end of the two-hour tour, we emerged into daylight, our chilled hands tingling in the summer heat.

The one-hour tours of Mystery Cave are held daily in summer and hold another set of oddly shaped wall patterns, evocative stalactites, 5-foot fossils — and bats, 2,000 of which hibernate in the cave. For many visitors, they’re the highlight, and on my tour, we could see furry little clusters of them snoozing in nearly every chamber.

Bats, explained naturalist Angela McKay, use sound waves to find mosquitoes to eat and obviously have no problem knowing where people are, as long as the people don’t move suddenly. We must have been listening, because when two bats started zooming around we just stood and watched.

“You’re much calmer than most people when bats are flying around,’’ McKay told us.

They weren’t the only residents of the cave. On lovely Turquoise Lake, its surface perfectly reflecting the ceiling, McKay pointed out white specks sitting on calcite rafts — springtails, a wingless insect that survives on lint and dead skin cells brought in by visitors.

Twenty-two miles southeast, less than a mile from the Iowa border, Niagara Cave traditionally has had the goofier tours, in the grand tradition of 1950s-style kitsch. But then former Rochester real-estate agent Mark Bishop, who has a degree in earth sciences, bought the cave and adjoining house and gift shop.

“Paul Bunyan moved out when I moved in,’’ Bishop said with a laugh, referring to the narrow ledge dubbed “Paul Bunyan’s bed’’ by previous guides. “I wanted the tours to be a little educational, and also fun.’’

Today, the cave glows with lighting so artfully arranged that each chamber and passageway has the shadowed elegance of an Ansel Adams photo. “I spent three winters up in the crevices, arranging the lights,’’ Bishop says.

Still, the cave has formations that really do look like an Elephant’s Head, a three-tier Wedding Cake and a battleship, and guides point them out. They also show visitors a frighteningly realistic, five-fingered skeleton’s hand: “Some guides, they’ll tell you this is what they’ll do to you if you touch the walls,’’ teased our guide, high-school student Amanda Bruggman.

When people touch a formation, their fingers give it a layer of oil that makes dripping water slide off, and the formation stops growing. That didn’t stop the boy in front of me from touching one — “Oh, who cares,’’ he muttered under his breath.

Niagara Cave also has a 60-foot waterfall, viewed from a suspended walkway; twisting Cathedral Dome, formed by a whirlpool; and a 625-foot Grand Canyon room — all features that make people say, “Wow.’’

My own favorite feature was a rock passageway, indented as if a giant had pressed his thumb into clay thousands of times. I’m also partial to the ribbon stalactites, also known as cave bacon, and the sharkstooth stalactites, fat on one side and skinny on the other.

In these caves, there’s a masterpiece around every corner. They weren’t created by chisel or brush, but a visitor’s reaction to them — awe — is always just the same.

Trip Tips: Southeast Minnesota caves

Getting there: It’s a two-hour drive to Spring Valley, 13 miles from Mystery Cave, or Preston, 18 miles from Mystery Cave. Niagara Cave is just west of Harmony, about 2¼ hours.

What to bring: A warm jacket and good walking shoes.

Niagara Cave: It's open daily May through September, weekends in April and October and otherwise by appointment. The one-hour tour costs $10.50, $9 for those 13-17 and $6 for those 4-12. The shady grounds include a pavilion and are a nice place for a picnic. To get there, drive 2½ miles south of Harmony on County Road 139, then two miles west on County Road 30. 800-837-6606, www.niagaracave.com.

Mystery Cave: Hour-long, half-mile tours of Mystery Cave are handicapped-accessible, on lighted concrete walkways, and are given daily between Memorial Day and Labor Day, weekends from mid-April through May and in October. On summer weekends, two-hour, one-mile afternoon tours are given of another section of the caves, known as Mystery 2 or Minnesota Caverns, where visitors carry hand-held lanterns. Visitors caravan from Mystery Cave to the entrance.

The entrance is five miles west of Forestville State Park. From Minnesota 16 between Spring Valley and Preston, take County Road 5 south for four miles, then drive two miles on County Road 118.

Cost for each tour is $10, $6 for children 5-12. A $5 state-park vehicle permit also is required. Call 507-937-3251, www.dnr.state.mn.us. The Forestville State Park number is 507-352-5111.

Historic Forestville: Within Forestville State Park, across from a little steel bridge, is a pocket of 1899, transported intact into the 21st century. Founded in 1853, the village of Forestville once was a place where farmers came to trade produce for goods and services at Thomas Meighen's store. The village began to fade after it was bypassed by the railroad in 1868, and Meighen eventually bought all the buildings and surrounding land. But in 1902, rural delivery was started, and neighboring farmers no longer had to go to the store to pick up mail. Meighen closed the store in 1910.

But his daughter Margaret sold it to the state, complete with inventory. Now, the store, along with Meighen's brick home, a wagon barn, granary and animal barn, is a living-history site operated by the Minnesota Historical Society. Costumed interpreters play real people, including Meighen's wife, Mary, and laborers Charles Ball and Charlie Martin.

It's open Tuesday-Sunday from Memorial Day through Labor Day and Saturday-Sunday in September and October. Special events include an 1899 Fourth of July celebration and typical "evenings of leisure'' as held in 1899. Admission is $6, $4 for children 6-17, plus a state-park vehicle sticker. 507-765-2785.

Accommodations: Harmony, Preston and Lanesboro have many accommodations, 800-247-6466, www.bluffcountry.com, often filled by bicyclists on summer and fall weekends.

Spring Valley, on U.S. 52, is closest to Mystery Cave. The Spring Valley Inn & Suites has nice rooms, 888-254-6835.

Last updated on July 6, 2008