The tunnel consists of two separate bores which carry four lanes of traffic between Cumberland Gap, Tennessee and Middlesboro, Kentucky.

The Cumberland Gap, a mountain pass that was important in American colonial history, is located at its closest point, about 0.4 miles (0.64 km) northeast of the tunnels.

Upon exiting the northern portal, the highway passes underneath the same railroad about 0.2 miles (0.32 km) later, before reaching a parclo interchange with a connector road to the park's visitor center.

The tunnels are equipped throughout their entire length and at each approach with closed circuit television (CCTV) cameras, which are connected to monitors in the control rooms.

[2] In 1916, the states of Tennessee, Virginia, and Kentucky constructed a road through the Cumberland Gap that connected to the Government Pike.

[2] As a result, the 2.3 miles (3.7 km) road through the Cumberland Gap quickly developed a reputation for having a high rate of traffic accidents, earning the nickname "Massacre Mountain".

During this time it was decided that widening the existing surface road to four lanes would adversely affect the historically sensitive areas in the park, making a tunnel the only viable choice.

A contract for initial construction activities was awarded on November 20, 1984, but the Administration of President Ronald Reagan abruptly issued an order to halt the project on December 14, 1984, reportedly in an effort to reduce the Federal budget deficit.

[9] During this excavation, workers discovered thick clay infillings, limestone formations, caves, multiple underground springs and streams, and a lake within the mountain, which caused a leakage of 450 US gallons (1,700 L) of water per minute into the tunnels would later pose a challenge to construction, and increase the cost of the project.

While the project was in the planning phases, Kentucky and Tennessee both began widening their portions of U.S. 25E leading to Cumberland Gap to four lanes.