National Milk Day is observed in the United States every January 11 to celebrate milk, a staple food rich in protein, calcium, and essential nutrients. The holiday's origins date back to 1915 when the International Association of Dairy and Milk Inspectors requested Congress to establish a National Milk Day, although it did not gain official recognition at that time. The date of January 11 is believed to commemorate the first delivery of milk in sterilized glass bottles by the New York Dairy Company in 1878. Celebrations typically include enjoying various milk and dairy products, such as milkshakes, ice cream, and cheese, as well as learning interesting facts about dairy and visiting local dairy farms. The United States is a leading producer of cow's milk, with over 40,000 dairy farms, particularly in states like California, Wisconsin, and New York. Other countries, such as India, also celebrate milk-related holidays, with India's National Milk Day observed on November 26.