A road vs high road

A road

noun
  • Any of many major roads in the United Kingdom, mostly multi-lane dual carriageways between cities 

high road

noun
  • A main road or highway. 

  • Used other than figuratively or idiomatically: see high, road. 

  • A course of action which is dignified, honourable, or respectable. 

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