It certainly depends. If you have a stretch where you build mostly at grade—you have maybe a few embankments, a small bridge, or a little river—you can say that in euros, at current prices, it's somewhere between 30 million euros to 40 million euros per kilometre. That would be around $50 million Canadian per kilometre. If you build in a more mountainous region, you go up from 80 million euros to somewhere around 100 million or 120 million euros. It really depends on the rock where you have to build the tunnel.
To give you a hint, you can say that if you build a tunnel, you can at least double the price of a rail system.