Built 1888 with two distinctive uphill grades beginning on either end, with apex 1,000 feet inside mountain. Caved in 1894 and rebored; caved in again in 1896 and rebored. Built underneath gap instead of through it, because the uplift of rock under Cumberland Gap was too steep to negotiate. Crosses from Claiborne County, Tennessee to Bell County, Kentucky, with entire Lee County, Virginia portion underground.
Tunnel under Cumberland Mountain on CSX Railroad at Cumberland Gap
Built in 1888 -1889 by the Powell's Valley Railroad; sold the same year to the Knoxville, Cumberland Gap and Louisville Railroad; sold in 1896 to the Louisville & Nashville Railroad. Now owned by CSX Railroad to connect Norfolk-Southern RR
Posted May 3, 2010, by CMountains (cumberlandmountains [at] yahoo [dot] com)
The picture is of the tunnel in Cumberland Gap, Tn (right next to the Iron Furnace parking area), but it's in the Cumberland Mountains not under Clinch Mountain. Clinch Mountain is a few miles southeast of this picture.