The Lyceum is the most monumental and one of the most dominant buildings of Eger, the bulk of which defines the inner city. On 29 June 1762, when Eszterházy Károly took the see of the bishop of Eger, thanks to his predecessor Bishop Barkóczy Ferenc, he was welcomed by the plans of the building of the university, prepared by Gerl József. In 1765, Eszterházy paid for Gerl’s work and commissioned Fellner Jakab to continue. However, the plan completed until then was not completely discarded, Fellner just reworked it. The original idea certainly did not include the chapel and the theatre. Another new element associated with the appearance of Fellner was the observatory.
By 1774, the Lyceum was in a state that could be considered for use. In October, Bishop Eszterházy ordered all the schools – theology, law and philosophy – to move there and teach their lessons there starting from the academic year 1774-75.