Floating City will be a four square mile structure that floats like an iceberg, with some of the surface structure visible above the surface, but most of the action happening down below the waterline. Built on land in large hexagonal sections, the pieces will be slotted together like a giant jigsaw puzzle in the ocean. Designed to be totally self-sufficient, Floating City will have its own farms and waste disposal systems, and will offer everything from housing to entertainment, sports complexes and shopping. Transportation will be provided using a series of underwater tunnels and submarines.
Before you cry foul and say that this will never happen, you should know that the proposal comes from the China Communications Construction Company (CCCC). These are the same folks who are currently building a 31 mile bridge connecting Macao to Hong Kong, so it's not like they're a bunch of noobs. That crossing also includes a lengthy underwater tunnel, which makes it sound like they have their water construction chops down too.