Westover Hall Location Position Ruler Appearance Westover Hall is a military academy in Bar Harbor, Maine where Grover Underwood discovered two demigods, Bianca di Angelo and Nico di Angelo. The principal was Ms. Gottschalk and the vice principal was Dr. Thorn. A rescue party - consisting of Percy Jackson, Thalia Grace, and Annabeth Chase - was sent to extract Grover and the new demigods, Nico and Bianca Di Angelo, undercover during a school dance.