A few folks asked me to post the build instructions for this beast. I created it in two halves. This is the bottom portion, the exact build requirements I'm not sure about, but it's a lot (I do know I used 20+ castle sets for the entire thing,though I think it's more like 10 for the bottom portion).
The bottom half was really just for show and isn't all that playable with the top half sitting on it.
Enjoy!
Note: The outline of the map (in Marvel concrete) was just a limit for me to stay within for the table size I had to build this thing, it is not intended to be part of the build.