A 3-line metro system called the "Metropolitana" operates in Rome. Construction on the first branch started in the 1930s. The line had been planned to quickly connect the main railway station with the newly planned E42 area in the southern suburbs, where 1942 the World Fair was supposed to be held. The event never took place because of war, but the area was later partly redesigned and renamed EUR (Esposizione Universale di Roma: Rome Universal Exhibition) in the 1950s to serve as a modern business district. The line was finally opened in 1955, and it is now the south part of the B Line.