If you're looking for a meeting place or a good stop around ½ or halfway between Columbus and Pigeon Forge, you can try Lexington-Fayette, KY, which is almost 3 hours southwest of Columbus, or a little over 3 hours north of Pigeon Forge.
Another possible place to stop near the midpoint is Richmond.
About ¼ or a fourth of the way, you can stop at Cincinnati, OH. This is about 1½ hours southwest of Columbus.
About ⅓ or a third of the way, you can stop at Florence, KY. This is about 2 hours southwest of Columbus.
About ⅔ or two thirds of the way, you can stop at Cooksburg, KY. This is almost 4 hours south of Columbus, or a little over 2 hours north of Pigeon Forge.
About ¾ or three fourths of the way, you can stop at Perkins, KY. This is a little over 4 hours south of Columbus, or almost 2 hours north of Pigeon Forge.
If you drive straight through without stopping at all, the total distance is 391 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 5 hours, 60 minutes.