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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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