The Taichung MRT (also called Taichung Mass Rail Transit or Taichung Metro) is a rapid transit system in Taichung, Taiwan. In addition to Taichung, it may serve Changhua and Nantou counties in the future. Taichung Metro's first route, the Green Line, officially began operation on April 25, 2021, making it the 5th rapid transit system operating in Taiwan. History Planning of the Taichung MRT started in 1990 with a study conducted by the Taiwanese Bureau of Housing and Urban Development. The study was completed in 1998 and suggested the implementation of three routes (Red, Green, and Blue). The project was formally approved by the Executive Yuan of the ROC government on 23 November 2004. The city government signed a joint development contract with the Taipei City Government on 12 December 2007. Meanwhile, the Taichung City Government started their own planning of more lines and decided that the much cheaper BRT system would be the future of mass transit in Taichung. Since the corridor of the originally proposed Red Line is partially served by the TRA mass transit construction, the Blue Line corridor was chosen as a first step to implement BRT in Taichung. Construction of the first line, the Green Line, had been paid for and was expected to begin in October 2007, though it was pushed back and started construction on 8 October 2009. The section of the Green Line was scheduled for completion by 2020 and includes 18 stations. On 9 March 2011, Kawasaki Heavy Industries announced that it had won a joint order with Alstom Transport SA (France) and CTCI Corp. (Taiwan) to supply 36 units consisting of two-car, driverless trains totaling 29.5 billion yen. While Kawasaki will oversee construction, Alstom will focus on signaling and CTCI will supply the electrical system. On 16 November 2020, the Green Line started trial runs. The first day of trial runs attracted more than 70,000 rides. The trial runs were suspended on 21 November 2020 when a railway coupler snapped in half. On 10 March 2021, Taichung Mayor Lu Shiow-yen (盧秀燕) announced that trial runs will resume on March 25, 2021, and the opening ceremony will be a month after. The Green Line officially began operation as scheduled on April 25, 2021, making it the 5th rapid transit system operating in Taiwan. Network Green line The Green line between Beitun and Wuri is an elevated railway with driverless electric trains.