What's silo?
Hmm. Now I'm seeing people that have captured, bred, and domesticated Bulettes, and use them to undermine buildings. If you have the time, creativity, and equipment, a castle isn't a big deal in D&D.
Silo 3D is 3d modeling software with a relatively low price point. It is only a modeler, though. It doesn't have any animation, rendering or effects features of the kind that make other 3d software like Maya or Houdini so cumbersome and expensive.
Bryan Ray, visual effects artist
http://www.bryanray.name
Actually, the gate at No. 2 concerns me more than No. 9.
Can a horse drawn cart or wagon make that turn?
If not, then the inhabitants spend a lot of time hand carrying supplies from the wagon outside the castle gate to the storage room near the kitchen … and those 50 gallon barrels are a bear to move.
The main gate (2) probably needs a straight approach.