Caves and Springs in Virginia

tourists entered Natural Tunnel, a large cave in Scott County, until a railroad built a track through it
tourists entered Natural Tunnel, a large cave in Scott County, until a railroad built a track through it
Source: Historical collections of Virginia, The Natural Tunnel (p.465)

Water created the 4,000+ caves in Virginia by dissolving limestone. Rainwater seeped down through the soil, becoming slightly acidic as it passed through decaying organic matter such as leaves. The acidic water slowly transformed the calcium carbonate - CaCO3, the predominant mineral in limestone and dolomite. Dolomite includes more magnesium than ordinary limestone, and is formed when magnesium ions replace calcium ions in the original limestone formation.

The chemical weathering created calcium bicarbonate - Ca(HCO3)2, which easily dissolved in water. Biological activity by sulfur-based microbial communities may also contribute, as at Cesspool Cave along Sweet Springs Creek in Allegheny County.1

As the calcium carbonate weathered away, the rock became pockmarked with voids and created a "karst" landscape with springs, sinkholes, caves. In Virginia, eroded remnants of cave systems are visible at Natural Bridge, Natural Tunnel, and Natural Chimneys. Acid rain may also be speeding up the creation of caves, by increasing the acidity of rainwater.

limestone layers are exposed by water-driven erosion at the Natural Chimneys the Cyclopean Towers in the 1800's
limestone layers are exposed by water-driven erosion at the Natural Chimneys, known as the "Cyclopean Towers" in the 1800's
Source: Henry Howe, Historical collections of Virginia (p.180)

The chemical weathering process is invisible when it occurs underground, but clearly visible in cemeteries aboveground. On old marble gravestones, once-clear letters have eroded away. The calcium in the marble (which is metamorphosed limestone) has dissolved in just a few decades, until the carved letters on many gravestones are no longer legible.

The Chimneys (including the Great Tower) were a tourist attraction even prior to the Civil War The Chimneys (including the Great Tower) were a tourist attraction even prior to the Civil War
The Chimneys (including the Great Tower) were a tourist attraction even prior to the Civil War
Source: Harper's New Monthly Magazine, Virginia Illustrated (February 1855)

Some minerals, such as silicon dioxide or quartz (SO2), are very hard to dissolve. The beach at Virginia Beach is formed predominantly from quartz sand grains, rather than calcium carbonate grains. Quartz is not very reactive; silicon dioxide is about the last mineral to dissolve, as rocks are washed down from the Appalachians. The quartz resists its inevitable fate of dissolving into the ocean. Granite headstones, with a high percentage of quartz and little or no limestone, retain their lettering longer than marble headstones.

The granite and metamorphosed lava in the Blue Ridge, and the sandstone ridges of Massanutten Mountain, are not riddled with caves like the limestone valleys in Virginia. In a few locations, rocks have fallen or eroded to create overhangs, crevices, and even a few spots that could be used as a shelter and perhaps labelled a cave.

hikers climbing up the Crabtree Falls trail in Nelson County will see a cave in the Blue Ridge created by fallen boulders
hikers climbing up the Crabtree Falls trail in Nelson County will see a cave in the Blue Ridge created by fallen boulders

Sand Cave, eroded into sandstone, is accessed by a trail from Ewing but is located in Kentucky
Sand Cave, eroded into sandstone, is accessed by a trail from Ewing but is located in Kentucky
Source: National Park Service, Cumberland Gap Historical Park

sinkholes and karst landscape features (brown lines) are common in the valleys with linestone bedrock, but not on Massanutten Mountain
sinkholes and karst landscape features (brown lines) are common in the valleys with linestone bedrock, but not on Massanutten Mountain
Source: Virginia Department of Conservation and Recreation, Virginia Natural Heritage Data Explorer

The metamorphic bedrock of the Piedmont and the sediments of the Coastal Plain also lack caves. No caves have formed in the sediments of the Triassic basins. There are only a few places in those regions where limestone or calcium-rich marl outcrops on the surface and caves might form naturally.

Where calcium carbonate (limestone) is the bedrock, caves will be more common. A map of cave locations in Virginia shows that nearly all the caves are west of the Blue Ridge, in the limestone of the Shenandoah Valley and in the equivalent valleys south of Augusta County. There may be cave-related museum exhibits in the Blue Ridge, Piedmont, or Coastal Plain physiographic provinces, but all the natural caves open to visitors are in the Valley and Ridge physiographic province.

the only site on the Virginia Cave and Karst Trail east of the Blue Ridge is the simulated cave exhibit at the Virginia Living Museum in Newport News
the only site on the Virginia Cave and Karst Trail east of the Blue Ridge is the simulated cave exhibit at the Virginia Living Museum in Newport News
Source: Virginia Department of Conservation and Recreation (DCR), The Virginia Cave and Karst Trail

Several caves are located in Loudoun County, east of the Blue Ridge. The caverns formed in the Leesburg member of the Balls Bluff siltstone, and that member includes a limestone conglomerate known locally as "Calico marble." The Leesburg member was deposited in the Culpeper Basin during the Triassic Period. The lakes in which the conglomerate accumulated after big storms must have been visited by dinosaurs, but no dinosaur fossils have been found in that limestone.

Over 1,200 feet of passage have been explored in Rust Cave #1 in Loudoun County. Sinkholes are common at Temple Hall Farm, and a "window" into an underground chamber is exposed on the east side of Route 15 just north of the entrance into the Raspberry Falls subdivision.2

The Loudoun County caves are named for the Rust family, whose brothers explored the caves after the Civil War in hopes of finding a "show cave" comparable to what was developed at Luray. At the time, the caves were called Big Cave and Eddie's Cave, after Eddie Rust. The mansion house Carlheim in Loudoun County was also built on top of a cavern.3

in 2020, the Carlheim mansion site was occupied by the Aurora School
in 2020, the Carlheim mansion site was occupied by the Aurora School
Source: ESRI, ArcGIS Online

Commercial caves attract tourists interested in seeing a unique environment with odd formations (speleothems). In caves with heavy visitation, stalactites, stalagmites, helictites, and other formations have been damaged. Many were broken as people initially explored caves, before paths were developed. Some formations were cracked off and taken home as souvenirs.

Before electric lights were installed in commercial caves, smoke from candles left soot on cave roofs. Creation of paths and installation of cables for electric lights transformed some cave passages. After lights were installed, algae grew on damp formations and altered their natural appearance. Efforts to remove algae with chemicals and abrasives created even more damage.

There are still thieves who consider cave formations to be items worth stealing. At the end of 2020, two men broke into Endless Caverns and stole formations which could be sold for over $1,000. They were arrested, but stalactites and stalagmites can not be glued back into place.4

Caves and cave formations can be dated using a variety of techniques. Caves formed after the limestone sediments were originally deposited, so caves west of the Blue Ridge are younger than the 570-350 million year old limestone formations in which the caves are found. The Taconic, Neo-Acadian, and Alleghenian orogenies destroyed whatever caves originally were created in those formations more than 200 million years ago. As the bedrock was squeezed and thrust westward by the accretion of terranes and finally the collision with Africa, any voids in the limestone formations that pre-dated the original Appalachian Mountains were squeezed shut.

Using the rate at which uranium decays, the age of speleothems can be determined. A stalagmite from Grand Caverns is 66,500 years old, so the cavity (cave) in which it formed must be older. Dating the mud watermark from a flood within Grand Caverns suggest the cave is at least 670,000 years ago.

Dates of caves can be estimated using the magnetic orientation of particles in cave sediments and the calendar of magnetic reversals over time. One passage in Buckeye Creek Cave, in West Virginia just west of Alleghany County, is at least 788,000 years old.5

New caves have been manufactured in recent times as well. There is one artificial cave in York County, which Cornwallis supposedly used before surrendering on October 9, 1781. Cornwallis' Cave is not a natural feature. That hole in the hillside was excavated as a shelter from French and American bombardment during the Revolutionary War battle.

gold miners created mines (artificial caves) in the gold-pyrite belt east of the Blue Ridge, stretching from Fairfax to Buckingham counties
gold miners created mines ("artificial caves") in the gold-pyrite belt east of the Blue Ridge, stretching from Fairfax to Buckingham counties
Source: Gigmaster, Virginia Gold Mine!

Artificial caves were constructed to age lager beer in Richmond. D.G. Yuengling Jr. opened James River Steam Brewery at Rocketts Landing in 1868. The cool conditions facilitated fermentation and storage of 6,000 barrels in the days before refrigeration. The brewery closed in 1879 and its building burned in 1891, but the caves have survived. Today they are visible from the Capital Cities bike trail, along the James River at the Richmond/Henrico County border.6

the James River Steam Brewery beer caves are still visible at Rocketts Landing, now on the border of Richmond and Henrico County
the James River Steam Brewery beer caves are still visible at Rocketts Landing, now on the border of Richmond and Henrico County

Later, other artificial caves have been built to store wine. The "cellars" ensure steady temperature conditions during the aging process.

The longest cave system in the world is Mammoth Cave in Kentucky, with 426 miles of mapped cave. The longest cave system in Virginia is the Omega System in Wise County, with over 29 miles of underground passages.

There are more than 80 cave systems in Virginia with at least one mile of passage. Eight caves in Virginia are at least 500 feet deep:7

Longest Caves in Virginia
RankNameCountyLength (in miles)
1Omega SystemWise County29.430 miles
2Sugar Run Cave SystemGiles County22.500 miles
3Chestnut Ridge Cave SystemBath County22.063 miles
4Gap Cave System (Cudjo's)Lee County19.884 miles
5Butler-Sinking Creek SystemBath County18.060 miles
6Perkins CaveWashington County9.997 miles
7Skydusky Hollow Cave System (Newberry - Bane - Buddy Penley Cave)Bland County9.000 miles
8Thompson Valley Cave System (Corkscrew Cave)Lee County8.600 miles
9Unthanks CaveLee County7.900 miles
10Stompbottom CaveTazewell County7.730 miles
Deepest Caves in Virginia
RankNameCountyDepth (in feet)
1Omega SystemWise County1263 feet
2Chestnut Ridge Cave SystemBath County814 feet
3Sugar Run Cave SystemGiles County718 feet
4Butler-Sinking Creek SystemBath County644 feet
5Doe Mountain CaveGiles County628 feet
6Thompson Valley Cave System (Corkscrew Cave)Tazewell County604 feet
7Dulaneys CaveGiles County601 feet
8Bullpasture Mountainside CaveHighland County519 feet
9Gap CaveLee County491 feet
10Seabolt-Spence Cave SystemSmyth County463 feet

Some caves found in Virginia have been impacted by modern development. Nellie's Cave Road in Montgomery County was built on top of the entrance to Nellie's Cave. After the Civil War, when the cave-exploring grotto club was first established at what is now Virginia Tech, a formerly enslaved woman known as "Nellie" and her husband Gordon Mills owned 100 acres which included the cave.

Nellie sold food to the cavers and people who picnicked at the cave entrance. Spelunkers would lower themselves on ropes into a cavern which reportedly stretched all the way to Cambria. According to the descendants of the Mills family, there was underground ballroom large enough for a fleet of school buses.

The entrance was sealed up when the gravel road was paved That was done, over objections by the Mills, to provide a highway for Woodland Hills residents.8

Nellie's Cave now lies beneath Nellie's Cave Road
Nellie's Cave now lies beneath Nellie's Cave Road
Source: ESRI, ArcGIS Online

Answers to Questions That Cave Guides Joke About

Cave Formations (Stalactites, Stalagmites, Soda Straws, Columns, Shields, etc.)

Commercial Caves in Virginia

Ecology of Virginia Caves

Geology of Cumberland Gap

Ground Water, Caves, and Temperature

Groundwater in Virginia

Limestone in Virginia

Thermal Springs in Virginia

The Role of Water in Birthing a Cave

Sinkholes and Cave Collapse

Springs in Virginia

sinkholes (brown lines) are not found in the Appalachian Plateau, but are common in the Valley and Ridge physiographic province
sinkholes (brown lines) are not found in the Appalachian Plateau, but are common in the Valley and Ridge physiographic province
Source: Virginia Department of Conservation and Recreation, Virginia Natural Heritage Data Explorer

Links

the entrance to Dixie Caverns is a functional structure with minimal esthetic appeal, and many stalactites in the commercial cave have been broken off
the entrance to Dixie Caverns is a functional structure with minimal esthetic appeal, and many stalactites in the commercial cave have been broken off

References

1. Annette Summers Engel, Megan L. Porter, Brian K. Kinkle, Thomas C. Kane, "Ecological Assessment and Geological Significance of Microbial Communities from Cesspool Cave, Virginia," Geomicrobiology Journal, Vol. 18 Issue 3 (2001), http://www.tandfonline.com/doi/abs/10.1080/01490450152467787 (last checked June 16, 2012)
2. "Minutes of the Fall 2000 VAR Meeting," Virginia Area Region (VAR) of the NSS, September 24, 2000, http://www.varegion.org/var/theVar/varMeetMinutes/minutesFall2000.shtml (last checked June 11, 2013)
3. "Digging into history of Loudoun's limestone overlay district," Washington Post, June 6, 2010, http://www.washingtonpost.com/wp-dyn/content/article/2010/06/04/AR2010060404575.html; Eugene Scheel, "History of Loudoun's Limestone Overlay District," History of Loudoun's Limestone Overlay District, https://www.loudounhistory.org/history/limestone-overlay-district/ (last checked January 29, 2020)
4. "Two Men Charged In Caverns Heist," Daily News Record, January 5, 2021, https://www.dnronline.com/news/two-men-charged-in-caverns-heist/article_04e58222-5b83-52b6-aaa9-20aef85e72c7.html (las checked January 6, 2021)
5. Gregory S. Springer, "Caves, Karst, and Science in the Buckeye Creek Cave Watershed," in Caves and Karst of the Greenbrier Valley in West Virginia, 2018, http://dx.doi.org/10.1007/978-3-319-65801-8_9; Dr. Dan Doctor, "Determining the Age of a Cave," Virginia Cave Owners Newsletter," April 2012, https://www.dcr.virginia.gov/natural-heritage/document/vacaveownersnewsletter24apr12.pdf (last checked January 15, 2023)
6. "Exploring Richmond's Beer Caves at Rocketts Landing," Richmond Style Weekly, February 18, 2016, https://www.styleweekly.com/RVAGrowler/archives/2016/02/18/exploring-richmonds-beer-caves-at-rocketts-landing (last checked October 18, 2020)
7. "USA Longest Caves by State," compiled by Bob Gulden, August 10, 2022, http://www.caverbob.com/state.htm; "Mammoth Cave just got a little more 'Mammoth'," National Park Service, September 8, 2022, https://www.nps.gov/maca/learn/news/mammoth-cave-just-got-a-little-more-mammoth.htm (last checked September 13, 2022)
8. "Answering the question: 'Mommy, I wonder if there is a Nellie?,'" Appalachian History, February 25, 2014, https://www.appalachianhistory.net/2014/02/answering-question-mommy-wonder-nellie.html (last checked March 14, 2024)

entrance to Weyers Cave (1872)
entrance to Weyers Cave (1872)
Source: Picturesque America (p.212)


Rocks and Ridges - The Geology of Virginia
Virginia Places