STIB/MIVB was created in 1954. The first underground tramway (or "premetro") line was built between 1965 and 1969, from Schuman to De Brouckère. In 1970, a second line was opened, between Madou and Porte de Namur/Naamsepoort. An underground station at Diamant was opened in 1972 and the "outer ring" line was extended from Diamant to Boileau in 1975. This underground tramway section has not been developed further, and it is used by tramway lines 7 and 25. Rogier station was inaugurated in 1974.