[tifik]

They use a tunnel boring machine to bore a tunnel with a 45° slope.

They do go into the mechanics of how they make this insanely massive machine drive up a grade that steep, and how they ensure it doesn't slide backward.

I was glued to the screen more than with most movies.

If you like channels like Practical Engineering, you will enjoy this.

[baq]

I watched this at 2x expecting a mildly interesting educational video. This was a mistake. Almost forgot to blink.

[em-bee]

I was glued to the screen more than with most movies

i was going to say something similar. this was better than the action movie i saw earlier.

[etrautmann]

Agreed - most interesting YouTube video I’ve seen in many months.