Lloyd Kahn worked as an insurance broker until 1965, then jumped into the counterculture’s DIY-building movement, edited the Whole Earth Catalog, and in 1973 published Shelter — still considered the bible of hand-built homes. He didn’t take up skateboarding until he turned 65. In a short video profile by Sierra Clark, he’s shown at 91 running, paddleboarding, and still riding, motion as habit rather than exception.