Gray, TN, used to be called “Gray Station”. There was a train station right about where the big telemarketing building is now. Just to the east of that location is the 41′ or so narrow ridge that the railroad had to tunnel through to maintain grade. Thus: what is known now as Free Hill tunnel. It’s a 472′ jobbie that quite a few people who work and live around the area don’t even know is there (and they probably don’t care, either). There are also two single-lane concrete railroad overpasses in the area, indicating that there were extant roads in the early 1920s (they also carry 1927 dates). But they didn’t carry a lot of traffic, or cars were a heck of a lot narrower then. Anyway, here’s the tunnel’s EC (west) portal.