Grab your pick axes, shovels, lanterns and canaries, and get ready to celebrate Virginia Cave Week in style by taking advantage of Virginia's glorious underground playground. The Virginia Cave Board is celebrating Cave Week from April 17-23, to educate the public about the importance of caves and other subterranean resources, some of which are closer to Ashburn than you might think.
"Cave Week started several years ago to celebrate the fact that Virginia is home to a lot of caves and to highlight the biological and geological diversity of those areas," said Dr. David Culver, Virginia Cave Board member, professor of environmental science at American University, and Loudoun County resident.
The Commonwealth is home to more than 4,000 known caves and caverns, many of which are located beneath the foothills of the Blue Ridge Mountains. These geological features form over the millennia as deposits of soluble rocks – such as limestone, gypsum, and dolomite – dissolve away when water seeps through the soil and onto the rock formations. The water then returns to the surface through rock fissures or enters the underground water table. The resulting hollowed out landscape, known as karst, can be highlighted by totally awesome caves and less awesome sinkholes that can devour roads, homes, and other structures above.
While the caves beneath the mountains of Virginia are well known, the Piedmont area of Loudoun County is also home to a significant karst landscape. Specifically, a swath of land that extends from south of Leesburg north and east to the Potomac River and west to the Catoctin Mountains sits right atop a large limestone deposit. The Loudoun karst features sinkholes and even some caves.
"The Limestone Belt in Loudoun County is quite unique. There are several small bands of similar limestone deposits in Virginia, but the Loudoun County belt is an unusual formation and has resulted in at least one large cave near Whites Ferry and several smaller ones in the county." Culver said.
Concern about the impact of development and pollution above the Loudoun karst led the Board of Supervisors to enact zoning and watershed management restrictions in the area known as the Limestone Overlay District in 2010. The restrictions are intended to protect the county's underground water supply and to ensure future development in the area takes into account the labyrinth of empty spaces beneath our feet.
Even with the maze of crevices possibly below us in Loudoun, Dr. Culver does not recommend setting off on your own spelunking adventure in the area. The few Loudoun caves he is aware of are located on private property and not made for beginners.
"Caving can be dangerous. The caves in Loudoun are interesting but not that inviting. They are composed of limestone that looks like a lot of small pieces of rock cemented together."
A better option for celebrating Cave Week is to check out one of Virginia's many commercial or "show" caves – such as Shenandoah, Luray, or Skyline Caverns – that are open to the public and within an easy drive of Ashburn. Many of these caves feature beautiful mineral and rock formations, some of which can only be found in Virginia.
If your adventurous side wants more than just a trip to a commercial cave, Dr. Culver recommends linking up with an experienced caving group, some of which can also be found locally.
"You can find information about caving groups on the National Speleological Society's website. There are caving groups in places as close as Front Royal that can help inexperienced and experienced cavers alike."