A massive composite workshop created by the utmost efforts of the most elite mages even among the many at the Family’s disposal—that was the Scladios’ main residence.
A variety of defense mechanisms and numerous evil spirits inside a powerful, thirty-five-layer ward.
In light of a case in which a mage’s workshop had been destroyed along with the building that contained it, its systems had been designed to defend against both airborne projectiles and attempts to destroy its foundations from deep underground.
For mystical defenses to surpass it, one would have to look to mage centers such as the Clock Tower or the Wandering Sea, or else the labyrinths and dens of vice that mages powerful enough to approach the Root had spent their lives constructing.

Fate/Strange Fake: Volume 5, Chapter 16 ("Breaking Dawn & Wakeless Dreams I")