A fantastic network of ocean cities on a water planet. There is no land anywhere. There are magnificient cities built on immense pylons. The cities are tall and have giant space ports on the top. Giant waves crash on the base of the pylons. The cities are connect by massive tubes that contain super highways for air cars and flying vehicles to get from city to city. The entire structure is vase and goes to the horizon. Done in a hard science fiction style with extreme details