Didn’t Mexico have one open do to an broken major water pipe that had been leaking for years? Didn’t anyone notice a water pressure drop in all those years. And doesn’t Florida get small sinkholes from the lime stone collapsing. I remember a house was falling into one and a brother ran in to save his brother in his room when he opened the door the brother was half in the hole and the most of the floor was gone. Like a good brother instead of trying to grab a rope, a curtain or something else he closed the door and let his brother and the house slowly fall into a bottomless pit.