Recently, new AFOL ook22 burst onto the scene with a great castle MOC, his Lake Hold Castle. He followed this up micro-style with the Haunted Keep.
This seems like a good time to celebrate micro castles with some older MOCs. A couple of years ago, Aaron Sneary posted his MINIcastle.
At a smaller scale, Mockingbird has a vig with a tiny castle as part of a Lowlug show.