Shenzhen Metro opens Line 7 and Line 9, China October 28, 2016 | Asia Pacific News Shenzhen Metro has started passenger services on Lines 7 and 9, which have together added 55.6 km (fully underground) and made the metro system the third largest in China with a total length of 285 km... This content is available to only subscribers. Username or E-mail Password Remember Me Forgot Password