This is a spawn for a multiplayer server and has walls built for TP signs and is a very wonderful place! an approximate 54 blocks in width and length and approximately 30--40 blocks tall! Also has a cute little cheeseburger on the inside.
It can also be a fun thing to put in your world if you collect giant builds(I don't know who would, but there's probably someone out there). You will have to download an MCEdit schematic to put it in your world. You'll need MCEdit for that.
http://www.mcedit.net/