railway vs railway line

railway

noun
  • A track, consisting of parallel rails, over which wheeled vehicles such as trains may travel. 

  • A transport system using rails used to move passengers or goods. 

railway line

noun
  • A group of railway tracks running parallel, allowing one track to be used for each direction (a double-track railway line), or allowing segregation of fast trains from stopping trains (a four-track railway line). 

  • A railway track; a pair of rails on which a railway train runs. 

  • An organization that runs a railroad. 

How often have the words railway and railway line occurred in a corpus of books? (source: Google Ngram Viewer )