Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

Oh, yep, I’ve no doubt that if they can ever actually get planning through for the damn thing, they’ll be able to build it. In Ireland it’s generally the planning that’s the problem.

What I’m curious about, though, is what, if anything, changed to make this single-bore approach suddenly popular. A lot of new metro lines seem to be built that way, but old (and not, like, 19th century, even most 20th century stuff) always seem to be double-bore.



One big factor for single-bore subway is that can fit the stations inside the tunnel. That saves a lot of money digging out the stations.

I think Barcelone Line 9 is the one that popularized it. I suspect the other factor is that they figured out how to make large TBM.




Consider applying for YC's Winter 2026 batch! Applications are open till Nov 10

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: