There have been two main periods of subway (or “metro”) building in the US. The first was during the late 19th century and early 20th century, when Boston, New York, and Philadelphia all built subway systems
Very interesting piece, thanks for writing. I grew up in the D.C. area and was always impressed by how a nation's capital could boast such a farkakte subway system.
Great piece! In the Construction section you have the reference "(US tunnels p185)". Could you add a link or more details to what that reference is referring to? I'm interested in learning more.
This is appalling