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CRT Line 6 (and the branch line branded as International Expo line) is the second heavy railsubway line in Chongqing, as well as being the longest rapid transit line in China, at 85.6 km (53.19 mi) long. It opened with provisional revenue service on September 28, 2012, and connects Nan'an, Yuzhong, and Jiangbei districts in central Chongqing.
Covering a distance of 6.7 km, this extension starts from Liujiaping station and branches off towards Chongqing East Station, with 2 stations in between. The project began on 28 March 2022.
The line crosses the Jialing River via Caijia Rail Transit Bridge (Chinese: 蔡家轨道大桥). Construction work began in October 2010 and it was completed in December 2013.