Whatever you call it, Amsterdam's got one and its about to get another line as well. The current route goes from Central Station out to the suburbs of Zuidoost. It was built in the late 1970s after masses of protest and much rioting. The Nieuwmarkt station has been decorated with photos of the protests.
Big efforts have been made in recent years to improve safety after the metro became notorious for its drug dealing.
The new line being built will connect Noord to the World Trade Centre. The chaos that is now the Rokin is part of it.