A couple of small R.R. Tunnels located in West/Central Indiana. ( 39°36'41.52" N 86°59'47.02" W ) ( 39°35'28.45" N 87°10'36.35" W )
Cool, hope to ride the entire 440 miles from Harlowton to Avery one of these summers. Not quite a tunnel unless you're a load of coal...
here is one of the tunnels near Avery....taken with a crappy camera, before I got a GoPro..... https://www.youtube.com/watch?v=OAxPeKunPHM
Riding through the underground poterns of XVIII-XIXth cent. Lysogorskiy Fort in the outskirts of Kiev:
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