Buckminster Fuller wanted to dome a chunk of Manhattan, but even that plan wasn’t as outré as his designs for a floating city. From “10 Failed Utopian Cities That Influenced the Future,” a fun i09 post by Annalee Newitz and Emily Stamm:

“Cloud Nine, the Floating City

Science — and science fiction — often influenced city designers. But nobody took futuristic ideas more seriously than mid-twentieth century inventor Buckminster Fuller, who responded to news about overcrowding in Tokyo by imagining cities in the sky. The Spherical Tensegrity Atmospheric Research Station, called STARS or Cloud 9s, would be composed of giant geodesic spheres. When filled with air, the sphere would weigh one-thousandth of the weight of the air inside it. Fuller planned on heating that air with solar power or human activity, causing the sphere to float. He would anchor his floating cities to mountains, or let them drift around the world. They were never built, but Fuller’s idea for a pre-fab, geodesic dome dwelling called Dymaxion House eventually influenced the pre-fab house movement which is still going strong.”