About National Deep Dish Pizza Day
To celebrate Chicago deep dish pizza—originated by Uno's—and the efforts by UNO Pizzeria & Grill to bring deep dish pizza to the entire United States. The original restaurant, which opened in 1943, began serving deep dish as a way to make sure hungry families could get a "real meal" when it came to pizza. Up to that point, pizza was hardly more than a snack.
Annually celebrated on the anniversary of the day (Apr 5, 1979) that the first restaurant outside Chicago opened (in Boston, MA).