This sounds good1, "The study and investigation of man-made and man used underground places".
Paul Clarke's blog - I live in A small town, Kent. Wed + dad to two, I am a full stack web engineer, + I do js / nodejs, some ruby, python, php ect ect. I like pubbing, running, eating, home-automation + other diy jiggery-pokery, history, genealogy, Television, squirrels, pirates, lego, + TIME TRAVEL.