West Qinling Tunnel

The West Qinling Tunnel (Chinese: 西秦岭特长隧道; pinyin: Xīqínlǐng Tècháng Suìdào) is in the middle of the Chongqing–Lanzhou Railway (Chinese: 兰渝铁路), crossing the Qinling Mountains. It is a 28236 meter dual-bore railway tunnel in Wudu District, Longnan City, Gansu Province, north-west China. It is the second longest railway tunnel in China, slightly shorter than the New Guanjiao Tunnel, which is also under construction. The construction started on August, 2008, and has gone on for duration of about five months and five years using both Tunnel boring machines (TBM) and drill and blast methods.

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