Not a billionaire but would love to start digging my own tunnels. [1] As for the billionaires, all the bunker's I've seen them build can barely just be called

Not a billionaire but would love to start digging my own tunnels. [1] As for the billionaires, all the bunker's I've seen them build can barely just be called a bunker. Most are mansions and some of them are even carbon neutral. [1] - https://www.youtube.com/watch?v=Ok2OPHg0660 https://www.youtube.com/watch?v=Ok2OPHg0660