The most serious threat to the existence of the Robie House arose 16 years later. On March 1, 1957, the Seminary announced plans to demolish the Robie House on September 15 in order to begin the construction of a dormitory for its students. This time an international outcry arose, and Wright himself, then 90 years old, returned to the Robie House on March 18, accompanied by the media, students and neighborhood organizers to protest the intended demolition of the house. Commenting on the threatened demolition, Wright quipped, "It all goes to show the danger of entrusting anything spiritual to the clergy. " Only weeks earlier, the Chicago City Council, led by Hyde Park alderman Leon Despres, had enacted an ordinance to create the Commission on Chicago Landmarks. On September 15, 1971, the newly formed commission, with the support of Mayor Richard J. Daley, declared the Robie House a Chicago landmark. Moreover, two fraternities at the University of Chicago provided the Seminary with a realistic alternative to its plans of demolition. During his very brief tenure as a student at the University of Wisconsin, Wright had been a member of the Phi Delta Theta fraternity. The University of Chicago's Phi Delt chapter house was located two doors north of the Robie house at 5737 Woodlawn Avenue, and the Seminary was already the owner of the lot between the two properties. The Phi Delts offered to vacate their house, and the Zeta Beta Tau fraternity, located next to the Phi Delt house, offered to vacate their house as well. These offers were a turning point in the effort to save the Robie house since the three properties provided the Seminary with sufficient land for the dormitory they sought to build.