Fantastic work, thanks for taking all those and posting them here! It's great to see all those. It looks like there is enough room to rebuild it, if they go beyond the berm to build a new Rainbow Caverns. There was some video I was watching recently, I think "Frontierland in Color," that shows the Mine Train going through the desert then entering the Rainbow Caverns. If a still could be captured from that, it could be compared to your photo of the tunnel entrance to see if that is the same entrance the Mine Train went in. It does look familiar.