Organ Cave in Greenbrier County, West Virginia, is a major historic and natural site whose surrounding community took its name from the cave. Part of the Organ Cave System, it was recognized for its preserved saltpeter workings and later listed on the National Register of Historic Places. The cave contains Ice Age fossils and evidence of early Native American presence, while a claimed 1704 inscription is doubtful. By at least 1835 it was mined for nitre, and Confederate forces under Robert E. Lee mined it again during the Civil War. Modern mapping began in 1948, and the system remains one of the longest known caves in the United States.