History of the Castle:
The castle was built about 100 years ago and has seen growth over the century. Once a small keep on the side of the hill, as time past it was realized the location offered significant strategic advantages in defense, commerce, and travel. This construction took place once the Orcs were driven back.
Little is known about when or how all the secret passages were constructed.
DM noted the well-documented taverns deep underground throughout the D&D world.