This tunnel unites Kermit and Speers Ferry VA in Scott County west of Gate City (see comment below). The tunnel is over 4,000′ long. This string is heading north. Just behind me and to the right is a curve that creates banshee-like shrieks as the wheels negotiate it (how do trains, without a differential, as such, handle curves? Read here.)

Correction on the state connection. This tunnel goes from Speers Ferry VA to Kermit VA. It is quite a few more miles before the track reaches TN.
You’re absolutely correct. I cannot explain why I thought Kermit was in Tennessee. Thank you for the comment.
My grandmother lived in Clinchport and would walk through the tunnel to Kermit where her family lived. The Winegars. She would take my mother and my uncle when they were just little. My grandmother has been gone a long time now but by mom is 91 And always likes to tell the Old Old Story.