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      How railway tunnel drilled on NW China plateau
      

      
Source: Xinhua|
Published: 2019-12-16

      

      
      
             
      
        
      
        
      
          
        
      
      
      
      
      
      

      
      
      
      
                        
      Click to see how the tunnel is built along the Golmud-Dunhuang railway on NW China plateau.
      
  
 
            
      
      

      

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