A tunnel under a mountain (how original)

So I started the mountain / tunnel. As you can see its all just pinned together as I see how its all going to fit together. Also, the tunnel is a lot bigger than I thought it would be. I guess the top down view in AutoCAD didn't do it justice. Oh well... the landscape is starting to look a lot more like its final contour.

As with the entire process all along, I've been doing track testing to make sure that the landscape I've been building up doesn't interfere with how the track has to go... and/or the track still fits around the landscape like it should.

Still debating on how much to use flex track, or how much to use pre-formed curve sections (a-la Atlas snap-track). I think mostly because I don't trust myself to make a perfect 22" radius or 18" radius curve, I'll go with mostly snap-track, with flex for the funny curves and straight-ish sections...