They're millions of years old, hundreds of feet below the ground and dripping with calcium carbonate formations. And many of them are just a day trip away from Baltimore.
Caverns are natural wonders carved out by underground rivers millions of years ago. Water that has seeped into the limestone caves creates formations that crystallize. The crystals come in many shapes and sizes: columns, ribbons, stalactites (hanging crystals) and stalagmites (crystals that grow up from the ground).
Below is a list of caverns found in Maryland, Pennsylvania, Virginia and West Virginia. For some cool relief (they all stay about 55 degrees year-round) from a hot August day, spend some time in a local cave and see what's going on down under (ground, that is).
Maryland
Crystal Grottoes Caverns, Boonsboro
Located about 75 miles outside of Baltimore in Washington County, Crystal Grottoes Caverns is the only "show cave" open for tours in the state. "Grotto" refers to a series of interconnecting underground pathways.
Surrounded by cornfields, trees and a quiet creek is an old stone building that houses the entrance. Old is a relative word - while the caverns have been forming for the past 250 million years, they were discovered on Sept. 18, 1920, when the State Roads Commission was quarrying for limestone to build up state Route 34. The landowners decided to commercialize the cave and opened it to the public in April 1922.
Since 1966, it's been owned by the family of Jerry Downs, who has been running the caverns for the past 17 years. It's a small, no-frills operation that aims to show off the natural wonders of the caverns and not much else.
Highlights of the tour include unique formations that resemble chandeliers, bacon, an Egyptian mummy, the U.S. Capitol building and a reflecting pool.
There are 26 stairs that take visitors 86 feet underground; a ramp back up leads to the building. Inside the caverns, the walkways are similar to sidewalks and make for an easy jaunt through the 1/7 of a mile tour.
Above ground, visitors can purchase rocks, gems and minerals that were excavated out of the caves and then lunch at the picnic tables by the creek. There's not much else to see in the immediate area, although the Antietam Battlefield is six miles away from Crystal Grottoes Caverns.
Hours: 10 a.m.-5 p.m. daily April 1-Oct. 31; 11 a.m.-4 p.m. weekends November-March; 30-minute tours run every 15 minutes.
