In 1982, a closed loop monorail line commenced operations at the resort island of Sentosa following the approval of plans to build it in 1979. The same year, the green light was also given to the construction of the Mass Rapid Transit (MRT) following a three-phase study conducted from 1972 to 1982 and a debate on an all-bus system against a bus-rail system. The initial MRT network opened in phases from 1987 to 1990, two years ahead of the original deadline of 1992.