This is madness. You're looking at a megalopolis made entirely in Minecraft using 4.5 million blocks over the course of two years on an Xbox 360 (!) Its name is Titan City and yes, it's completely insane, especially when you get up close:
The city was created by Duncan Parcells, an art student interested in interactive design who goes on Xbox Live as ColonialPuppet. He actually made all this on the Xbox 360, which is particularly crazy on itself:
[...] all the blocks were hand placed on the map since it's Xbox but I have over a dozen or so PC buildings set aside for when it's moved to PC for good and those collectively took like a couple hours with Minecraft edit. I guess the medium is part of the message in this case.
The city once finished on Xbox, will be permanently moved to PC and made even larger.
He said he didn't make it on a PC, where it would have been infinitely easier, because he only had the Xbox 360 version when he started: "Minecraft wouldn't work on my Mac for some reason but recently I got a PC for college and now I have it on both".