There is a distinct connection between the agricultural potency of the Pennsylvania Dutch Country and the three commercial caves located within it — limestone. As Germans flooded into the region in the early 18th century, fleeing wars and seeking land, they quickly settled on what would become some of the most productive farm land in the world. They surveyed the landscape and noted where the oak trees grew the biggest and the underbrush the thickest. They looked for well watered land with an abundance of springs and streams upon which to forge a new life, in a new world after a long and often deadly Atlantic crossing. This prime acreage they found mainly in the valleys and more often than not the bedrock beneath their farms was limestone whose chemical composition was ideal for the creation of mineral rich ultra-fertile topsoil. Another characteristic of the limestone was it’s tendency to form the low lying, rolling topography in between ridges of more resistant shale and sandstone. These edenic lowlands not only gave rise to world class soil but also to a very distinctive type of landscape known as karst.
Caused by limestone’s chemical vulnerability to solutionally aggressive rain water, karst landscapes are typified by the presence of sinkholes, sinking streams, large springs and caves. The Pennsylvania Dutch Country is home to hundreds of caves, thousands of springs and tens of thousands of sinkholes. Most of the caves are small in size when compared to other karst regions in United States, but none the less would’ve been notable features of the local landscape. Some of them however are large enough to constitute well know landmarks.
One in particular had been known of for as long as Europeans had been active in the region. Known today as Indian Echo Caverns, this large cave whose entrance opens onto the Swatara Creek 10 miles east of Harrisburg was originally deeded to a Hugh Hays in 1754 from the proprietors of the Pennsylvania colony.The cave was known then as the Swatara Grotto and most likely had been attracting visitors for a half century or more. Prior to the arrival of Europeans in the late 17th century it is likely that the local Susquehannock Indians knew of the cave existence although there is no archaeological evidence that they entered or used it in any fashion. Originally being an offshoot of the Iroquis from New York State the Susquehannock were believed to have conquered and assimilated Indians already living in the Susquehanna river valley in the 1300’s. These earlier tribes, who would never know any contact with Europeans, certainly would of been aware of the large entrance to the cave that would’ve been reachable via a six mile canoe trip up the Swatara Creek. Paleo-Indians inhabited the area for thousands of years prior to the era that witnessed the first contact between Europeans and the Suquehannock, so it is possible that the cave was first entered by humans several thousand years ago.
Being relatively large in volume and length as well as generously endowed with eye catching depositional features like stalactites, stalagmites and flowstone it is not surprising that the Swatara Grotto, known as Hummelstown Cave or Echo Cave by the late 19th century, would eventually become a modern tourist attraction. But it wouldn’t be until 1929 that necessary modifications were made to the cave’s interior to allow curious visitors to safely navigate the subterranean passages and see with the help of electric lights what earlier explorers would’ve seen with the aid of torches, lamps and candles. But by the late 1920’s, as Indian Echo Caverns was giving it’s first commercial tours, another Pennsylvania Dutch Country cave would’ve already been in operation as a successful tourist attraction for nearly 60 years.
Crystal Cave, located 5 miles east of Kutztown in Berks County was discovered in November of 1871 and in less than one year was operating as a successful tourist business. In doing so it became the first “commercial” cave in the state and further more, one of Pennsylvania’s first bona fide tourist attractions. But it was just one of three significant caves that would go on to become full blown tourist attractions discovered in Pennsylvania Dutch Country between the years of 1871 and 1883. What links these caves together historically is not just their geographic proximity but also the specific mode of their discovery. In all three cases the people who discovered the caves did so quite by accident while undertaking the an activity whose purpose was related directly to agriculture. Namely the small scale quarrying of limestone.
As noted earlier the connection between agriculture and caves in the region is based upon the chemical composition of the rock itself. Under proper climatic conditions limestone breaks down on the surface to create excellent soil for farming and, beneath the surface it is highly susceptible to the formation of networks of interconnected voids of varying sizes that essentially serve as natures plumbing, moving water under the effects of gravity from point A to point B. Another characteristic of limestone is that when it is burnt under specific conditions at a temperature between 900 and 1000 degrees celsius it undergoes a chemical transformation know as calcination whereby calcium carbonate (limestone) decomposes to calcium oxide (quicklime) and carbon dioxide. The resulting quicklime that is created by burning chunks of limestone in a kiln has many uses, one of which is as an soil additive know as ag-lime.
Ag-lime is generally used to increase soil pH, which can increase crop yields among a wide range of soil conditions. Ag-lime is often used to improve the physical structure of the soil by reducing surface crusting, increasing water retention, and reducing soil erosion. Lime treatment helps crops to better tolerate drought and wet conditions by increasing both root penetration and water percolation through the soil. Using ag-lime to adjust pH in soils can reduce toxic levels of manganese, iron and aluminum. In addition to the above, ag-lime has been shown to increase herbicide effectiveness, increase nutrient availability to plants and add calcium to soil. (source)
Local, small scale quarrying to source limestone for the creation of ag-lime was common throughout the region prior to it’s availability as a mass produced product from industrial scale quarries. Many farmers would simply find a good outcropping of limestone on their property and begin by collecting the loose rocks on the surface followed breaking off chunks with sledgehammers and pickaxes. The use of black powder charges was a powerful way to speed up the process of extracting the raw limestone directly from bedrock. It was during the course of blasting into hillsides and ridges in this fashion that Crystal Cave, Lost River Caverns and Onyx Cave were discovered. In fact hundreds of caves of varying sizes and appeal were accidentally discovered across Pennsylvania (and the country as a whole) during the times leading up to the advent of industrial scale quarrying. These three in particular just happened to be of a size and interest that warranted their subsequent development into tourist destinations. This historical fact alo brings to light the fact that many caves that exist in the region never had naturally occurring entrances large enough, and obvious enough to allow easy access to humans. Indeed there still, to this day, exists many miles of undiscovered cave passages, not only in Pennsylvania Dutch Country but across the state as a whole, wherever limestone is exposed at the surface in a fashion conducive to the development of karst and it’s attendant geomorphological landforms. After the onset of industrial scale quarrying and the availability of cheap, mass produce ag-lime, farmers were relieved of the need to undertake labor intensive work of quarrying and burning their own limestone, and the accidental discovery of caves, on a farm by farm basis, ceased entirely as a result .
Having been a participant in the first serious exploration of the cave, local farmer and rock hound Samuel Kohler saw the potential in the property and by March 1872, only five months after it’s discovery, had managed to buy 47 acres that included the cave from owner Gideon Merkel for $5000, or what would be approximately $95,000 in today’s money. Kohler officially opened the cavern to the public in May of 1872 charging an admission price of ¢25 per person. By 1876 he had quit farming to focus on business and had built a two story hotel on the site to accomodate the increasing number of visitors who arrived by rail to nearby Virginville. Kohler’s son David took over operations when he died in 1908 and successfully managed the cave for the next 14 years. By 1922 the number of yearly visitors had reached a record 24,000. David Kohler sold the business that year at the age of 57 to a group of investors from Reading.
Although discovered less than a year after Crystal Cave, the cave that would be know commercially as Onyx Cave lay dormant for 60 years as the its ownership changed hands. Eventually opened in May of 1923 by Irvin Dietrich, a year after Crystal Cave was sold, Onyx cave was sold and resold eight times, eventually closing to the public in 1984. Despite being a large and attractive cave it was ultimately a failure in business terms. One reason being the fact that nearby Crystal Cave had had 60 years to establish itself as the premier cave tour destination in the area. Onxy Cave is far from being the only Pennysylvania commercial cave to have shuttered it’s chambers to the paying public. Scattered throughout the state there are no less than 12 former show caves that, for various reasons, did not manage to survive as ongoing business concerns.
The third cave in our trinity of accidental discoveries – Lost River Caverns, has managed to survive and has been open since May 24, 1930. Located in Hellertown, south of Bethlehem in Northampton County and only a mile from Interstate 78, the cave was discovered in 1883 after blasting in a quarry owned by Charles Rentzheimer revealed a narrow fissure in the bedrock. The fissure had been blasted open years prior but it was only with further blasting that it became large enough to permit entry by a human. In 1886, the quarry was leased to a man named Zeno Weirbach who, along with his son, made a brief trip into the cave but got no further than the sun’s rays streaming in through the entrance would allow. It would be up to Charles Weidner to push the cave beyond the twilight zone and in doing so explore for the first time the main parts of the cave today that are seen by visitors. After an account of Weidner’s adventures was published activity and interest in the cave increased dramatically and by 1888 a platform for dancing had been installed in one of the cave’s larger rooms, local college students toured the cave to study it’s geology and to perform fraternity initiation’s. By the 1920’s the land where the quarry was located was owned and operated by Bethlehem Steel as a source of flux for their blast furnaces. Although quarrying operations were ongoing the cave was apparently spared from destruction during that period. With the onset of Prohibition the cave was reportedly leased out to local bootleggers to be used as a secret storage facility for illicit liquor.
The caves wild days were to cease suddenly when it was purchased in 1929 by Erwin and Marie Gilman, a couple from Philadelphia who, after having toured Crystal Cave decided that they wanted a cave of their own to develop into a tourist attraction. Their search ultimately ending when they toured the already well known cave near Hellertown that was famous not only for it’s size and formations but also a subterranean stream of unknown origin that ran through the cave’s length, a feature that Crystal Cave, Onyx Cave and Indian Echo Caverns could not lay claim too. A year of modifications including the laying of stone walkways, pouring of concrete steps and the installation of electric lights and handrails was needed before the newly christened ‘Lost Cave’ was opened to the public at large.
Around the same time that Lost River Caverns was under development, 75 miles to the east near Hummelstown Indian Echo Caverns was also coming to the end of it’s time as a well known wild cave. Dr. U. S. G. Bieber and D.M. Ryan bought the cave and the farm above it and invested $125,000 in order to transform the cave and the property into a commercial venture. In the first six months of operation forty thousand people paid to tour the caverns. In 1931 more modifications were made to the cave in the form of a 50 tunnel blasted through solid bedrock at the end of the North Canyon passage in order to extend the tour to newly discovered room whose beauty justified the considerable expense incurred by the blasting. Despite early success, both Indian Echo and Onyx Cave succumbed to the economic impact of The Great Depression that settled across the country after the stock market crash of 1929.