(Yicai Global) Jan. 2 -- China added a record 969 kilometers of track to urban metro lines last year, new data from the China Association of Metros showed. At the end of 2019, 40 cities had opened subway lines, stretching a total of 6,730 km.

Five mainland cities -- Wenzhou, Jinan, Changzhou, Xuzhou and Hohhot -- opened their first urban rail transit systems last year, and 27 increased or extended routes, with 26 newly opened and 24 sections lengthened.

On Dec. 28, the eastern extension of Beijing Subway Line 7 as well as its Batong section opened for trial operations, putting the total length of the capital's metro system at 776 km. Hefei Subway Line 3 and Guangzhou Metro Line 21's extended section opened on Dec. 26 and Dec. 20, respectively.

Shanghai still has the longest set of metro tracks in China at 801 km, followed by Beijing with 776 km and Guangzhou with 501 km. Some 15 cities, including Chengdu, Nanjing, Wuhan, Chongqing, and Shenzhen, operate over 100 km each.

Networks in second-tier cities have developed rapidly in recent years, and are struggling to catch up with those in first-tier cities. Chengdu has proposed to have 500 km this year, and Hangzhou plans to have 516 km before the Asian Games in 2022.

The National Development and Reform Commission approved new urban rail transit construction plans in Chengdu, Xi'an and Zhengzhou last year. The approved lines have a total length of 486 km, with an investment of CNY342.6 billion (USD49.2 billion), according data from the China Association of Metros.

Editor: Dou Shicong