catacomb vs cellar door

catacomb

noun
  • An underground system of tunnels and chambers with recesses for graves, used (in former times) as a cemetery; a tunnel system used for burying the dead, as in Paris or Ancient Rome. 

cellar door

noun
  • A door leading to a cellar. 

  • In phonaesthetics, a quintessential example of an inherently pleasant-sounding phrase irrespective of its meaning. 

  • Part of a winery from which wine may be sampled or purchased. 

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