A walk through the crypt-like bowels of Slotsholmen, known as Ruinerne under Christiansborg, offers a unique perspective on Copenhagen's well-seasoned history. In the basement of the current palace, beneath the tower, are the remains of two earlier castles. The most notable are the ruins of Absalon's fortress, Slotsholmen's original castle, built by Bishop Absalon in 1167.
