IF railroads are your thing… I should invite you up to BC sometime.
Up here everyone has all but forgotten about the railroads… and the fact that some of the longest railroad tunnels in the world are here in British Columbia, and that many of the railroad systems that were built pre-ww2, were built with defense in-mind, connecting all the major civic buildings etc.
Hundreds of MILES of these railroad tunnels lay derelict under Vancouver/Burnaby and the surrounding regions, and no one talks about them. Never a -Subway- system, just traditional rail.
I’ve heard of a tunnel in the rockies that it so long, it has comparment doors and ventilation to keep oxygen in the tunnel, and that entire TRAINS dissappear into the tunnel and pass through the opening and closing compartments, insane feats of engineering - long forgotten.
That’s what I know about whats just in my backyard… and we’re small time up here… I can only imagine what YOU know!