IN AUGUST 2004, the Gisler family -- Tam and Hans, their children Genevieve, Luke and Gabriella, then ages 14, 12 and 7, and their 90-pound Bouvier dog -- left Anchorage in a 29-foot motor home to travel across North America for nearly a year to broaden their knowledge of the United States and its neighbors and enjoy family time.
Most Americans have no idea how many beautiful and intriguing caves there are to be explored all over our country. Many are part of the national park system, some are privately owned, and others are on state land but not well known.
WIND CAVE
We visited Wind Cave National Park, in the southern Black Hills of South Dakota, shortly after Labor Day 2004. Upon arriving at the visitor center, we easily purchased tickets for the next cave excursion. Since summer crowds had dwindled substantially, we were told our off-season tour would be much more relaxed and enjoyable.
We began by watching a film about the park and learned that the cave started forming 320 million years ago. Native Americans knew about Wind Cave for generations and considered it sacred.
The cave received its name in 1881 when two brothers, Jesse and Tom Bingham, heard a loud whistling noise. They followed the sound to a small hole in the ground where they discovered a wind with such a force that Jesse's hat was blown off his head. The wind is created by the difference in atmospheric pressure in and outside of the cave.
We descended a narrow staircase deep into the earth for the fascinating 90-minute ranger-guided Natural Entrance Tour. At the lowest point, we were 200 feet underground; obviously, this is not a recommended tour for claustrophobes or people who have fear of depths.
We learned that in a one-mile radius, there are more than 168 miles of discovered tunnels. Fortunately, we only had to follow the dimly lit blacktop path for about half a mile. The temperature is 53 degrees year-round, so with jacket or sweatshirts on, we were neither hot nor cold.
Wind Cave is devoid of water and therefore has very few stalactites and stalagmites but many other unusual formations. We observed boxwork, the thin honeycomb-like structures of calcite that protrude from the walls and ceilings. This is one of the few caves where boxwork formations can be found.
We marveled at the popcorn and frostwork formations, which look like their names imply. We enjoyed being at the front of the tour line as we snaked through passageways, ducked through the rocks and peered into dark tunnels veering off in every direction.
In one cave room, the ranger extinguished all the lights so we could experience total darkness, a truly spooky feeling. At the end of the tour, we ascended to the surface in an elevator.
We decided it would be fun to return in the summer and participate in the special 3,000-foot tunnel exploration that requires crawling on your belly and knees for three to four hours! Another future trip will include Jewel Cave National Monument, located about 30 minutes from Wind Cave and known for its calcite crystals.
LURAY CAVERNS
At the beginning of December 2004, we visited the marvelous Luray Caverns in Virginia's Shenandoah Valley, located below the Blue Ridge Mountains. Taking a tour of these privately owned caves allowed us to see some absolutely stunning stalagmites and stalactites.
(Here's a memory trick to differentiate between the two: stalagmites MIGHT reach the ceiling some day; stalactites hang TIGHT from the ceiling.)
As we followed the paved lit paths, the guide shared several intriguing stories about the various formations. The "fried eggs" looked like they are named; the shiny "yolk sack" was caused by thousands of hands rubbing the surface and leaving skin oils.
The towering stone columns, the icicle and lace-like formations in natural colors of red, yellow, blue and green, as well as the crystal-clear pools, were all very beautiful.
These subterranean chambers range from 30 to 140 feet high and as much as 500 feet in length. In one of the largest rooms, called the Cathedral, we were entertained by a "stalacpipe organ," purported to be the world's largest musical instrument, covering more than three acres.
The organ was devised and built over three years by Leland Sprinkle. It plays symphonic-quality notes by tapping rubber-covered mallets on stalactites of varying sizes, which were selected for their musical tones. This room is often rented out for weddings.
The temperature in the cave remains at about 56 degrees year round, offering respite from both winter cold and summer heat.
In earlier times, the purity of the cave's air prompted a man named T.C. Northcott to lease the cavern and build an above-ground home for people with respiratory ailments. He invented a shaft and fan system to circulate the cavern air throughout the house with much medical success. Luray Caverns is a treat for the eyes, ears, nose and skin!
MAMMOTH CAVE
At the end of January 2005, we explored Mammoth Cave National Park, 90 miles south of Louisville, Ky. We boarded a park bus at the Visitor's Center and traveled to the "new entrance" on the Frozen Niagara Tour.
Our two rangers guided us down 250 feet through very narrow staircases and passageways until we stopped in a room named Grand Central Station. We learned about the history of the cave, which was first discovered and mined for salt from 4,000 to 2,000 years ago by Indians. Several mummies were discovered in the cave in addition to a well-preserved male who was smashed flat by a 600-ton rock.
The caves were rediscovered in 1798 and mined for saltpeter during the War of 1812. The ranger explained that the tunnels and cave were made by carbonic acid formed when rainwater infiltrates the soil and mixes with carbon dioxide gas. This acid dissolves the highly soluble layers of limestone, which were formed from sediments of a shallow sea that covered this region 350 million years ago.
She pointed out that this carbonic acid is a weaker version of the potent carbonic acid contained in modern soft drinks. If its weaker solution can form caves, just think of the amount of calcium that soft drinks leach from teeth and bones!
As we continued through the cave for three-quarters of a mile, we began to realize that Mammoth Cave was nowhere near as beautiful as those caverns we've already seen. Only in the Frozen Niagara area did we see stalactites and stalagmites, as well as the popcorn similar to Wind Cave. There is also a lot more green algae growing on the formations because of the artificial lights installed in the cave.
However, Mammoth does win the distinction for 350 miles of surveyed passageways, more than twice as long as any known cave in the world. Geologists estimate that there could be as many as 600 more miles of passageway yet to be charted.
Mammoth also holds a diverse cave ecosystem with 130 forms of life, most quite small. There are numerous species of bats; we saw one hibernating that was no bigger than a thumb. Many of the creatures like the cavefish and the cave crayfish are eyeless and colorless because they live in darkness. We also saw some cave crickets and cave worms.
This was the only tour available on that winter day, so we wondered if others would have been more impressive. I noted on the map that there was a room named Mount McKinley on another excursion as well as the ruins of an old tuberculosis hospital. We watched a film about the caves in the visitor center and then went to look at the historic entrance, a sink hole close by.
CARLSBAD CAVERNS
In March, we visited our last cave in New Mexico. Carlsbad Caverns National Park is another must-see. We chose to take the Natural Entrance self-guided route, which we were told was similar to walking into a steep canyon.
At the Natural Entrance, we observed the amphitheater where, on summer nights, one can see 300,000 Mexican freetail bats in search of insects speed out of the cave at a rate of 5,000 bats per minute.
We followed the path inside this entrance and felt the temperatures quickly drop from 90 degrees outside to 56 degrees inside. We gingerly noted the bat and sparrow guano which punctuated the smell of the caves.
We hiked a mile and a quarter, and 800 feet down, to the Big Room. (The back of my calves sure hurt later on!) The spaciousness of these caverns was astounding. They are big enough to contain 14 football fields. The ceiling measures 255 feet high in this area of the cave.
We took a self-guided circular tour of the Hall of Giants, the Bottomless Pit and the Top of the Cross, marveling at all of the beautiful and varied formations. I wished we'd had more time to take other tours in these caverns.
We stopped at the gift counter in the Underground Rest Area and purchased both postcards and stamps. Gabriella wrote a postcard to a friend while I prepared others for my parents and ourselves. The "mailed from 750 feet underground" imprint they bear proves that this is the deepest mailbox in the United States!
We boarded the elevator to ride the 75 floors to the surface, very happy that we didn't have to walk back up!
We haven't been to any caves in Alaska, but I learned there are many in Southeast Alaska, especially on Prince of Wales Island, bearing names like Blowing in the Wind Cave, El Capitan Cave and Lawyer's Cave. We recommend visiting any and all caves. These buried national treasures are educational and fun to explore!
If you go
• WIND CAVE NATIONAL PARK (1-605-745-4600, www.nps.gov/wica); tours, $3-$20; tickets first come, first-serve
• LURAY CAVERNS (1-540-743-6551, www.luraycaverns.com); tours, $8-$17
• MAMMOTH CAVE (1-270-758-2180, www.nps.gov/maca); tours, $2.50-$46; reservations at reservations.nps.gov or 1-800-967-2283
• CARLSBAD CAVERNS (1-505-785-2232, www.nps.gov/cave); reservations at 1-800-967-CAVE; self-guided tours, $3-$6; guided tours $8-$20
