1. http://www.us-highways.com/cgap00.htm Old 25 E: Crossing the Cumberland Gap, includes Cumberland Gap related links.

2. http://sherpaguides.com/tennessee/upper_cumberland_plateau/cumberland_gap.html Sherpa Guide: "Longstreet Highroad Guide to the Tennessee Mountains" by Vernon and Cathy Summerlin.

2. The Phoenix of the Mountains by Joseph E. Suppiger. (Harrogate, Tennessee: Lincoln Memorial University Press, 2001). 3rd edition.  Information about Cudjo's Cave:

pgs. 31-32:

Another attraction is the cave which is variously known not only as "King Soloman's" and "Cudjo's," but also as the "John A. Murrell Cave," and, simply "Gap Cave." The latter designation was given this subterranean curiosity until about 1890, when the desire for tourism on the part of businessmen caused it to be given the imaginative name, "King Solomon's Cave." Some local people, however, stubbornly continued to call it the "John A. Murrell Cave" after an infamous Tennessee outlaw from Claiborne County. In more recent years, a portion of King Solomon's cave has been opened to regular tours and is called "Cudjo's" after a fugitive slave who, it is said, found a place of refuge in this natural hide-away. One of the earliest visitors to the Cave was the nation's famous conservationist, Gifford Pinchot. Then governor of the state of Pennsylvania, Pinchot remembered reading a story by James Trowbridge about a place called "Cudjo's Cave," and was thrilled by his "discovery"--it was a discovery to be made by thousands more.

The entrance to Cudjo's Cave is located midway between Cumberland Gap village and the Pinnacle Overlook on highway 25-E (The old Virginia Highway). Within, one may find a clear pool called the "Wishing Well," a "petrified forest," a "Ball Room," "Frozen Cascades," the "Pyramid," the "Ancient Cathedral," and almost countless other sights. This attraction, owned by the University, is efficiently operated by others under a lease.

p. 76:

In 1934, Cudjo's Cave was opened to the public. Plans were also made for the creation of a park out of LMU's Seiberling Tract. With this in mind, the Cumberland Gap Historical Association was founded, which finally achieved its primary objective in 1955 with the establishment of the Cumberland Gap National Historical Park.

p. 143:

Cudjo's Cave at the Cumberland Gap, an auxiliary enterprise of the University, was sold [to] the National Park Service for a more natural restoration once the new tunnel (completed after seventeen years of work by the Park Service and the Federal Highway Administration) permitted the highway to be removed.

The dedication of the Cumberland Gap Tunnel, a project which had cost $239 million, took place on October 18, 1996.