>>520489118
>>520489536
I tried to replicate the methodology I thought they used and came up with pic related.

This map includes all kinds of bullshit that's not even buildings.
As an example all the bullshit like this >>520487172 is included. Compare to the map in the OP, I didn't go all out with diligence, I might have missed a difference.
In addition, there's shit like bunkers made in 2009 in this map. The reason I limited the area so much is that these queries aren't exactly instant.

I'm going to query for things that are actual buildings and have a meaningful classification as a defensive castle, fortification, or palace.