One of the oldest and most deeply felt traditions in Alatri, historically the city's first major produce market after summer, marking the start of a new agricultural cycle. The medieval centre fills with colorful stalls of onions, garlic, chili peppers, dried legumes, honey, cheese, oil, and wine, while participating restaurants create special onion-themed menus. The fair runs into the night in continuity with the September 8th feast of the Madonna della Libera, the city's co-patron saint.