To contrast, HS2 here in the UK has cost £40 billion (€45 billion) to date with a further £25 billion (€28 billion) allocated, for a largely superterranean route of 230km.
Would be interesting to read how the Austrian project was contracted out? It seems in the UK the big construction companies have got very good in extracting a lot of money from customers, wonder if things were different in Austria with this project.
In contrast, the 2nd Ave Subway extension here in NY cost $4.5 billion for 2.9 km
7x longer for 11x the cost seems pretty good all things considered.
Always thought it seemed like a waste to not also dig out a bunch of storage while we're down there. I'm sure there are good reasons we don't
As badly as HS2 has been run, apart from the tunnel length (where HS2 has not too much more than this project) these projects are night and day different. Not just that HS2 Phase 1a/1b is almost double the length and significantly higher design speed (360km/h vs 250km/h), but they are in a different league in terms of civil engineering from the info I can see - this seems to have less than 80 structures (overpasses, bridges, underpasses etc.) whereas HS2 has 175 bridges and 52 viaducts, and some of those are massive (including the longest railway viaduct in the UK).