CRECGZ completes drilling of second-longest tunnel of China–Laos Railway June 21, 2020 | Asia Pacific News The China Railway Guangzhou Engineering Group (CRECGZ) has completed the drilling works of the second longest tunnel of China–Laos Railway. The tunnel spans 9.26 km and is located in Oudomxay Pr... This content is available to only subscribers. Username or E-mail Password Remember Me Forgot Password