The Arba'een Pilgrimage constitutes a religious phenomenon with extensive social and ethical ramifications, producing a rare collective state grounded in harmony, behavioral discipline, and positive human interaction among millions of pilgrims from diverse backgrounds. This event acquires its intellectual significance when approached through the concept of the Ideal City, as a philosophical conception of a society whose relationships are organized on the basis of supreme values and shared ends. The research focuses on analyzing the most prominent manifestations of peaceful coexistence in the Arba'een Pilgrimage and linking them to the principles of the Ideal City, to reveal how spiritual values are transformed into living social practices. Adopting the descriptive-analytical method, the findings show that the Arba'een Pilgrimage produces an integrated model of peaceful coexistence based on an ethical system that intersects with the principles of the Ideal City; mutual respect is embodied in disciplined behavior governed by the sanctity of the event, and fraternal unity is crystallized in the dissolution of ethnic and social differences within a unifying spiritual bond. Altruism and solidarity manifest in unprecedented forms of giving and selflessness, and cooperation appears as an act grounded in value rather than interest. This is accompanied by intellectual purity, collective awareness enabling self-organization, and spiritual interconnectedness that reshapes relationships on the basis of shared meaning and purpose. The research affirms that the Arba'een experience approximates the image of the virtuous society where ethics and values take precedence over individual interests.