The problem in old cities isn’t as much that they can’t get through old stuff, but more that they don’t want to because of archeology.

For an example, see the Bosphorus tunnel in Istanbul (https://www.theguardian.com/world/2006/jan/25/turkey.iantray..., https://en.wikipedia.org/wiki/Marmaray#Delays)

A huge find, unfortunately on the location where a terminal was planned.