The National Radio Quiet Zone (NRQZ) is a large area of land in the United States designated as a radio quiet zone, in which radio transmissions are restricted by law to facilitate scientific research and the gathering of military intelligence. About half of the zone is located in the Blue Ridge Mountains of west-central Virginia while the other half is in the Allegheny Mountains of east-central West Virginia; a small part of the zone is in the southernmost tip of the Maryland panhandle.

The Allegheny Mountain Range, informally the Alleghenies, is part of the vast Appalachian Mountain Range of the Eastern United States and Canada and posed a significant barrier to land travel in less developed eras. The Allegheny Mountains have a northeast–southwest orientation, running for about 300 miles (480 km) from north-central Pennsylvania, southward through western Maryland and eastern West Virginia.