Talk:Buildings/@comment-9998583-20131028100941/@comment-76.171.222.183-20131108061117

Under the "Ward" section, you'll notice that the unlock requirement is to Complete Campaign 8-6.

After you do this, you simply need to build a "1st Kingdom Gate" which only costs 1 gold / 1 ether / 1 iron. (Basically free)

After that you have access to your "2nd Kingdom". The plot of the 2nd kingdom is as large as your first one completed maxed out. However, there are debris in the way you have to clear which costs a lot of resources. Hope that helps.