In 1995 the Madrid Metro spanned 71 miles, ranking 51st worldwide. Over the next 12 years it added 126 miles, tripling its network and placing it among the fastest‑growing systems alongside Beijing and Shanghai. Today it ranks sixth longest outside China and third in Europe after London and Moscow. The expansion linked the airport, added a circular line and connected suburban towns, boosting ridership.

The 35‑mile push from 1995‑1999 cost about $2.8 billion (2024 dollars), a price New York paid for a 1.5‑mile extension and far below London’s Jubilee Line, which spent nearly ten times more per mile. The World Bank called Madrid’s spend ‘substantially below internationally possible’ levels. Cost savings came from 24/7 tunneling and standardized station designs.

A key driver was the Community of Madrid’s control over planning, funding and construction, enabling rapid, accountable delivery. Its regional assembly levied taxes and approved an €25 billion transport budget—68 % higher per‑capita than London’s—while the regional consortium oversaw the metro, light rail and buses. This authority let politicians tie electoral promises to concrete extensions, producing a sprawling, cost‑effective network that attracted private contractors seeking stable contracts.