Sculpted from the Earth over a hundred million years, Mammoth Cave is a daunting labyrinth of contorted tunnels, passageways, vertiginous shafts and cathedral-like chambers – all immersed in darkness. This subterranean wonderland of towering limestone pinnacles and glittering gypsum is a place in which to marvel at nature’s artistry – or get lost in forever.
Indeed, the underground tunnels that comprise Mammoth Cave (properly known as the Mammoth-Flint Ridge Cave System) are known to extend for at least 400 miles beneath the rugged karst hills of central Kentucky. Mammoth is, in fact, the longest known cave system on the planet – twice as long as Mexico’s Sac Actun.
Moreover, it is a place of staggering biodiversity – possibly the richest subterranean ecosystem on Earth. No less than 130 species of flora and fauna inhabit its network of underground conduits, including some totally colorless and truly weird creatures that have never seen sunlight.
Geologically, the cave is composed of two main strata. The upper stratum is porous sandstone, and the tunnels at this level have a relatively simple appearance. Beneath them, however, layers of limestone have slowly and unevenly dissolved with the drip of percolated groundwater. The result? Otherworldly cavities and grand sculptures of stalactites and stalagmites.
The discovery of mummies inside the cave indicate that it was used by the region’s indigenous inhabitants in pre-Columbian times. Much later, in the late 18th century, it was mined for saltpeter, also known as potassium nitrate, one of the key ingredients in gunpowder. Curiously, however, it was not until the mid-19th century that any attempt was made to investigate its deepest recesses.
Enter Stephen Bishop, a mixed race slave who from the age of 17 was considered the property of Franklin Gorin. In 1838 Gorin acquired the Mammoth Cave with the aim of developing it as a tourist attraction. And, working for Gorin as a guide, Bishop soon proved himself an able and fearless spelunker.
He was, after all, no mere slave. According to an account of his character penned by Gorin, Bishop was a “self-educated man… a fine genius… A great fund of wit and humor… [he had] some little knowledge of Latin and Greek, and much knowledge of geology… His talents were of the first order.”
The young man was apparently quite handsome as well. “He is very picturesque,” wrote Nathaniel Parker Willis, whom Bishop once guided during an expedition. “With more of the physiognomy of a Spaniard, with masses of black hair, curling slightly and gracefully, and his long mustache, giving quite an appearance.”
But above all else, Bishop was an explorer. And while he was permitted to survey the cave at will, he soon found himself at a threshold. This was the so-called bottomless pit – beyond which other guides refused to pass. Plunging beyond the light of a lantern, this vast and gaping chasm marked the known limits of the Mammoth cave system at the time.
Still, undaunted, Bishop went to cross the pit in 1838 with an equally intrepid tourist. Using a long wooden ladder, he created a bridge over the chasm, gripped a lantern in his teeth and made his way across – very carefully. After all, one slip would have meant certain death. When he reached the other side, however, what he discovered would earn him a place in history.
“Grand, gloomy and peculiar” was how Bishop described the subterranean world he found. There were rivers and eyeless fish, snakes and noiseless crickets. And in 1839, a year after his crossing, both he and the cave fell under the ownership of Dr. John Croghan, who also relied on Bishop’s exploratory knowledge.
In 1840 Bishop then made his most impressive discovery to date – the 192-foot-high Mammoth dome. And, a year later, accompanied by John Craig of Philadelphia and Brice Patton of Louisville, he located a cave encrusted with glittering gypsum and named it Cleaveland Avenue. In fact, Bishop had named most of the sites in the cave using a mix of classic and familiar references, such as the River Styx and Gorin’s Dome.
To gain a better understanding of the system, Croghan had Bishop draw the cave’s first map in 1842. It was published by Morton and Griswold in 1844 and showed roughly 10 miles of tunnels – half of them discovered by Bishop. Furthermore, although the map was not perfectly to scale, it was clear that the magnitude of the cave system was like nothing else.
In 1849, however, Croghan died of tuberculosis. And, seven years later, under the terms of his will, Bishop was granted his freedom. Apparently, he had at one time talked of buying the freedom of his wife and son and traveling to Liberia, a self-declared independent nation of freed slaves.
But in 1857, just one year after he was freed, Bishop himself died, most likely also of tuberculosis. His headstone was donated by a banker, James Ross Mellon, who met Bishop’s widow while visiting the region in 1858. It simply read, “Stephen Bishop, First Guide and Explorer of the Mammoth Cave.”
Meanwhile, around the start of the 20th century, the region succumbed to the so-called “Kentucky Cave Wars” – a period of intense rivalry among local cave owners. During this time, newly arrived visitors were often misled by incorrect highway signs and scammers telling them that Mammoth Cave was inaccessible.
Then in 1909, Max Kämper, a German mining engineer, spent several months conducting a detailed survey of the cave, helping to locate new entrances. More scientists followed, and in 1912 French explorer Édouard-Alfred Martel took barometric measurements that identified the elevations of multiple levels within the cave. Hence, year by year, understanding of the system grew.
Not surprisingly, biologists have identified a number of rare animal species inhabiting the cave, including at least five species of bats, two different genera of crickets, two more of eyeless cave fish, a cave shrimp, a cave crayfish and a cave salamander. And so, far from being a still and deathly place, Mammoth Cave is actually full of curious life.
Due to the cave’s unique ecology, then, it made sense to protect it. Subsequently, in 1926, the National Park Service began acquiring lands in Kentucky for the purpose of creating The Mammoth Cave National Park. In 1941, the park was officially dedicated. It even gained international recognition in 1981 as a UNESCO World Heritage Site. Then in 1990, it was dedicated as an international Biopshere Reserve.
Today, Mammoth Cave National Park sees some two million visitors annually. For those who wish to tour it, a number of options are available – the most adventurous of which involve crawling through mud. You can even visit the bottomless pit. And though the chasm’s depth has now been gauged at 105 feet, it still manages to evoke a powerful sense of terror.