Over the next ten years, "New York will spend $4.5 billion on a 1.7-mile line under Second Avenue. Los Angeles will get a 8.6-mile extension to the Westside for $6 billion. And Barcelona will have built 30 miles of automated subways for €6.5 billion ($7.9 billion according to today's exchange rate).
The new 'L9' metro line will expand the cities network by one third and include 52 new station, 22 of which will be transfers. The line is incredibly deep to avoid disrupting the current system and construction makes use of Spain's specialization in tunnel boring technology.