Since the beginning of time, people have lived in caves. But few have ever built one. Junya Ishigami, a Tokyo architect who goes to extremes, is one of them. In 2003, Ishigami launched his practice with the design of razor-thin metal tables for a friend’s restaurant. Coming back for seconds, the same chef asked Ishigami for a new building combining his home and a new restaurant. This time, the client wanted to go “heavy.” And he wanted to go “old.” Unsurprisingly, these requests led Ishigami to an unconventional solution.