Yes, it was another of poor old Union General John Wilder’s failures (see: Cloudland Hotel): the Charleston, Cincinnati & Chicago Railroad (the “Triple C”). Begun in 1886, his railroad was doing great until it all went bust in 1893, leaving behind a partially completed rail bed from Johnson City (the railroad’s headquarters) to near Dante. Confusion ensued until, about 1902, George Carter managed to acquire parts of the old Triple C. He went to work upgrading the line: reducing grades, easing curves and putting what would be the Clinchfield Railroad on its way. In the process, portions of the previous rail bed were abandoned when better locations were developed. That’s the rail bed you refer to. There’s another stretch right at Slant VA. As I recall, Calvin Sneed tells that it’s called “Slant” because the land there was unstable and required much work to make the rail bed stick in one place instead of sliding into the river, creating a slant. There’s a fine truss bridge across the river there.
Blogging the Railroad Tunnels 
Could you tell me the name of the railroad that was never finished on the North Fork Of the Holston River near the Hawkins County , TN. state line.
Yes, it was another of poor old Union General John Wilder’s failures (see: Cloudland Hotel): the Charleston, Cincinnati & Chicago Railroad (the “Triple C”). Begun in 1886, his railroad was doing great until it all went bust in 1893, leaving behind a partially completed rail bed from Johnson City (the railroad’s headquarters) to near Dante. Confusion ensued until, about 1902, George Carter managed to acquire parts of the old Triple C. He went to work upgrading the line: reducing grades, easing curves and putting what would be the Clinchfield Railroad on its way. In the process, portions of the previous rail bed were abandoned when better locations were developed. That’s the rail bed you refer to. There’s another stretch right at Slant VA. As I recall, Calvin Sneed tells that it’s called “Slant” because the land there was unstable and required much work to make the rail bed stick in one place instead of sliding into the river, creating a slant. There’s a fine truss bridge across the river there.