Was that part of the 'Midland RR'? It started in Colorado Springs roundhouses and went west thru the state to Utah I think. Lots of trails and tunnels to follow when I was a kid......we use to leave gas cans under bridges and then run the old rr beds and passable tunnels on dirt bikes.....absolute ball.....well maybe the alcohol and being young helped ....but still lots of fun.:victory::wings:Both of them were outside of Buena Vista, CO. The tunnels is part of an area called "Fourmile" (Let me tell you it is more than that LOL)