Luray Caverns

Series of limestone caves in Page county, northwestern Virginia, U.S., near the town of Luray (headquarters of Shenandoah National Park). Covering 64 acres (26 hectares), the caverns, discovered in 1878, were formed millions of years ago by underground rivers and seepage of acid-bearing water through layers of limestone and clay. In time the clay was washed away, leaving only the limestone