> I wonder if the French are considering digging underneath all those obstacles Paris has been doing it for decades. All new lines in Paris (such as metro line

> I wonder if the French are considering digging underneath all those obstacles Paris has been doing it for decades. All new lines in Paris (such as metro line 14, opened in 1998, RER E) have been dug by tunnel boring machines, and are at a depth below 20m. Same goes for all new lines outside of Paris proper, like most of the Grand Paris Express 200km+ new lines.