Having just stayed in Milan for a week i was really impressed with how the metro had been built and continually improved. I wanted to know though, how was the

Having just stayed in Milan for a week i was really impressed with how the metro had been built and continually improved. I wanted to know though, how was the tunnelling done so cheaply? I noticed the lines seemed to follow roads a lot, did they do cut and cover along the roads to keep costs down?