Borromeo Castle was the home of King Orrin, the ruler of Surda. It was built on a rise at the capital, Aberon. The citadel sprawled out across the land and was protected by three concentric layers of walls, along with numerous towers. The parapets were lined with hundreds of manned ballistae, in the event that a hostile dragon should attack the castle.
Borromeo Castle contained King Orrin's large, smokey laboratory: it was where the king held council with his advisors. While the Varden were staying in Surda, Nasuada was given living quarters within the castle, with soldiers guarding the door. Other members of the Varden housed in the castle were Farica (Nasuada's handmaid), Elva, Greta (Elva's caretaker), as well as Angela. Nasuada recalled staying in the castle when she was a child and Orrin's father ruled.
The name Borromeo is the surname of Saint Charles Borromeo, who was born in 1538 and died in 1584. He was a cardinal of the Roman Catholic Church and leader in the Council of Trent.
Saint Charles Borromeo is the patron saint of apple orchards, bishops, catechists, catechumens, seminarians, spiritual directors, spiritual leaders, starch makers, Lombardy, Italy, Rocca di Papa, Italy and the diocese of Monterey, California. He is invoked to assist in the cure or prevention of ulcers, colic, intestinal disorders and diseases of the stomach.
A fan named Mike Fynan supposedly gave the castle its name.