The research describes the projective principles of illusory space of the Bolognese School through the representation of the architectural perspectives of Girolamo Curti (1575-1632) and Angelo Michele Colonna (1604-1687) at the town hall of Bologna. In 1627 Cardinal Bernardino Spada was commissioned by Pope Urban VIII to drive the Bolognese delegation; he started the renovation of his apartments through the illusory artifice of perspective. In addition to the sala Urbana and the sala del Dentone, Colonna, a pupil of Curti, will become the protagonist of a long artistic season; he was also active in Spain where at the initiative of Diego Velázquez, he worked at the Court of Philip IV. Returned from Madrid he left his last masterpiece paintin...