If you do not have this book, "Railroad with 3 Gauges" is worth owning if you can find it. Dave McNeil did the book, and I went with him a time or two on his researching what was left. This of course is the Cincinnati, Georgetown, and Portsmouth railroad you mentioned.
There is a short line operator currently running on NS tracks from Clare Yard to somewhere east of Winchester, I believe. The line was severed east of Peebles. Apparently NS did not want to upgrade the big bridge over the Scioto River outside Portsmouth (Vera), so they sorta mothballed it several years ago. A sad state of affairs, that was terminated when CSX and NS split up Conrail. NS Got a more direct line from Bellevue and Columbus to Cincinnati at that time.
I did two videos on the Cincinnati-Portsmouth line, called Norfolk Southern's Peavine, and a volume 2. These were done in the nineties.
Greg