The Blue Ridge is a mountain chain in the eastern United States, part of the Appalachian Mountains, forming their eastern front from the Carolinas to New York State. To the west of the Blue Ridge, between it and the bulk of the Appalachians, lies the Great Valley.

Most of the rocks that form the Blue Ridge Mountains are ancient Granitic and metamorphosed volcanic formations, some exceeding one billion years in age. The slow, steady forces of wind, water, and chemical decomposition have reduced the Blue Ridge from Sierra-like proportions to the low profile of an old mountain range. By comparison, humans have been associated with this land only about 9,000 years.

The Blue Ridge Parkway extends 469 miles (750 km) along the crests of the Southern Appalachians and Links two eastern national parks: Shenandoah and Great Smoky Mountains. In many places along the Blue Ridge Parkway, there are metamorphic rocks (gneiss) with folded bands of light-and dark-colored minerals, which sometimes look like the folds and swirls in a marble cake.

Although the term "Blue Ridge" is sometimes applied exclusively to the eastern edge or front range of the Appalachian Mountains, in which range Grandfather Mountain is the highest peak, the geological definition of the Blue Ridge province extends westward to the Ridge and Valley area, encompassing the Great Smoky Mountains, the Great Balsams, the Roans, and other mountain ranges.

The range itself extends north into Pennsylvania; New Jersey, where it is known as the Kittatinnies; and lastly into New York where it becomes the Shawangunks.

The highest peak in the Blue Ridge and the Appalachian chain is Mt. Mitchell in North Carolina at 6,684 feet (2037 m). There are 39 peaks in North Carolina and Tennessee higher than 6,000 feet; by comparison, the northern portion of the Appalachian chain contains only one 6,000 foot peak, New Hampshire's Mt. Washington.

The Brushy Mountains in North Carolina are a "lost" spur of the Blue Ridge Mountains.