Here is the verse:
Rev 21:16 : 16 And the city lieth foursquare, and the length is as large as the breadth: and he measured the city with the reed, twelve thousand furlongs. The length and the breadth and the height of it are equal. KJV
I always pictured the city itself as a cube, since the walls are mentioned separately. Do you all not see it that way? I ask because I am going to require considerable space for my mansion. :)
And who will keep it clean, FK? Big houses are a big problem (LOL). mxxx