September 3 Holidays

Skyscraper Day marks September 3, 1892, the birthday of Louis Sullivan — the Chicago architect known as the “Father of Skyscrapers” who articulated the principle “form follows function” and mentored Frank Lloyd Wright. Foundation Day in San Marino is the national day of the Republic of San Marino, founded by Saint Marinus on September 3, 301 CE — making it the world’s oldest republic and one of its smallest nations, landlocked entirely within Italy. National Welsh Rarebit Day celebrates the savory sauce of melted cheddar, ale, mustard, and Worcestershire poured over toast — a dish recorded in English cookbooks as early as 1725 but whose origin in Wales is disputed by culinary historians. Merchant Navy Day is observed in the UK on September 3 to honor the merchant mariners who have served in wartime and peacetime supply chains. Steel and glass, 301 CE, a cheese-sauce dispute, and a cargo ship.