The Vase, the Needle, the Angel, the Guard: Don’t be misled by their simple names — these sedimentary rock formations in the Punkva Caves are among the most extraordinary in the world.

Punkva, located in the Czech Republic’s Moravian Karst, a nature preserve, which measures more than 38.5 square miles, is the largest and most significant karst system in the country. There, 350 to 380 million years ago, water dripped, flowed and pooled on limestone, eroding it to create streams, springs, shafts, fissures, sinkholes and caverns filled with geological wonders.

There are more than 1,100 documented caves in the Moravian Karst. Nature, the consummate sculptress, has outdone herself at Punkva, the best known and most visited of the five caves that are open to the public. The combined length of the known corridors is about 3 miles; you’ll explore about three-quarters of a mile during a guided one-hour tour.

Professor Karel Absolon — a Czech archaeologist, geographer, paleontologist and speleologist — is credited with discovering the Punkva Caves in 1909. Descending into the unknown through a hole that had been hidden among boulders, he and a colleague picked their way gingerly across uneven floors, crouched beneath low ceilings and balanced on rock ledges.

Of finding the very first chamber, Absolon later wrote: “We’re drawn to a small hole. Jesek stands on my shoulders, gets through the hole and then hauls me up. We crawl on our bellies through the canal — now we can crawl on our knees, we call out and there is an echo and suddenly we wonder — can it be true?

“We catch our breath with astonishment. In front of us is a huge space. We call again and our echo dies out somewhere far, far back. Where the searchlight is able to shine we can see a fantastic bayonet- shaped stalactite and at the back there are white walls! With the help of our reflectors we can make out that the walls are, in fact, covered with many protruding dripstones. We are absolutely amazed. … A memorable moment of historical importance in the research into the Moravian Karst has come.”

Absolon and his team completed their work in 1914, and many other scientists followed; in fact, fieldwork in Punkva continues to this day. Some sections of the caves opened to the public in 1910. Tours have included a boat ride since 1933; renovations over the years have equipped the route with paved paths, lighting, sound systems, rust-proof railings, viewing areas and emergency telephones.

What draws 200,000 visitors to the Punkva Caves every year? Sculptures, magnificent natural sculptures — too many to count, no two exactly alike. The Needle, for example, is a 10-foot stalactite that’s just 2 inches from the stalagmite directly below it. They have also been dubbed Romeo and Juliet.

Two stalagmites, the Vase and the Dwarf, were created when water percolated through stone high above them and gradually flattened their tops. The Angel, a stalagnate, resembles a heavenly being with outstretched wings. Stalagnates are formed when a stalactite and a stalagmite meet or when a stalactite reaches the floor of a cave. An entire stage of spectacular forms is reflected in aptly named Mirror Lake.

The adventure continues on the boat trip along an underground segment of the Punkva River. Be alert: Some of the passageways are low (if you’re tall, you’ll have to duck) and narrow (at times, there’s just a foot or two to spare on either side of the boat).

You’ll disembark to see Masaryk’s Dome, named after Tomas Garrigue Masaryk, who was instrumental in founding Czechoslovakia and became its first president. Of note here are straw stalactites that are long, hollow and thin — no more than a half-inch in diameter.

Impressive, too, is the Macocha Abyss, adjacent to the caves. This breathtaking cathedral is as long as two football fields. Its walls rise 454 feet — some 40 stories — and when the tour guide plays a recording of the motet “Ecce Quomodo Moritur Justus,” all conversation yields in rapt silence.

In short, a visit to the Punkva Caves is at once enthralling and educational — a rare glimpse of the wonders nature has wrought far beneath Earth’s surface.

Czech Republic celebrates centennial

When the Austro-Hungarian Empire collapsed at the end of World War I, Czechoslovakia was established from several of its provinces. The new democratic republic was born on Oct. 28, 1918, two weeks before the war officially ended.

During World War II, Czechoslovakia was occupied by Nazi Germany, freed by the Red Army and ceded to the Soviet Union in June 1945, three months before that conflict ended. The Communists rose to power in the Soviet Union in 1948, and Czechoslovakia was a satellite Communist state for the next 41 years.

After the fall of the Communist regime in 1989, Czechoslovakia again became a democratic republic. On Jan. 1, 1993, it separated peacefully into two countries, the Czech Republic and Slovakia.

Among the centennial events planned in the Czech Republic this year are food festivals, art exhibitions, sports events, dance presentations and concerts. Visit czechtourism.com or czechandslovakcentury.com/en.

There will even be a performance by the Czech Philharmonic Orchestra and the Prague Philharmonic Choir at New York’s Carnegie Hall on Oct. 28, the 100th anniversary date. For more information, call Czech Tourism’s United States office at 212-288-0830 in New York, email newyork@czechtourism.com.