Republic Day, also known as the Feast of San Marino and the Republic, is a significant national holiday observed in San Marino every September 3. This day commemorates the foundation of the republic in 301, attributed to the legend of Saint Marinus, who fled from the Diocletianic Persecution of Christians and established a new city near Monte Titano. Celebrations begin with a solemn mass, during which the relics of Saint Marinus are paraded through the streets. Following the official ceremonies, the festivities become more communal, featuring events such as a crossbow tournament, concerts, and a popular bingo event. The day is marked by a blend of religious reverence and cultural celebration, reflecting the rich history and traditions of San Marino.