Today, April 7, marks the 77th anniversary of the beginning of one of the most raucous 24-hour periods in American history. It was on this day in 1933 that Congress officially modified the Volstead Act, better known as the National Prohibition Act, which in 1919 had made it illegal to manufacture, sell, or transport any beverage containing more than .05% alcohol. The modification rose that to 3.2%, and, as the day neared, the breweries around the country that hadn’t been driven out of business in the dry, 14-year period (they survived by making drinks like root beer and ginger ale), readied for what would become one of the wildest national parties in American history:

At 12:01 a.m. on April 7, 1933, brewery whistles around the country heralded the return of beer. Throughout the night before (fondly dubbed “New Beer’s Eve”), jubilant beer drinkers lined up outside breweries, anxious for their first taste of legal beer. In Milwaukee, where crowds were said to have been 50,000-strong at the breweries, beer drinkers hauled away their precious kegs and cases in everything from wheelbarrows to baby carriages. In New York City, movie houses played the newly-released film, “Beer Is Back!” Around the country, night clubs, hotels and restaurants—most filled beyond capacity—struggled to keep the taps flowing as raucous crowds downed an amazing 1.5 million barrels of beer during the first 24 hours that beer was back.

Patrons at a Chicago restaurant hoist their mugs for a newspaper photographer in April 1933 to celebrate legislation allowing the production of beverages with an alcohol content of up to 3.2 percent.

1.5 million barrels of beer. In 24 hours. I think we should all note on our calendars that tomorrow marks the 77th anniversary of what was known at the time as “OWWWWWW Day.”

So here’s to your health, bottoms up, cheers, here’s mud in your eye, down the hatch, and all that, and Happy Anniversary, Beermerica. May there be many, many more.

Extras: The Volstead Act gave the 18th Amendment, prohibiting the manufacture, sale, or transportation of “intoxicating liquors,” the full force of the law, and was necessary to define what “intoxicating liquors” were. The 18th Amendment itself was not repealed for another several months, on December 5, 1933, with the passage of the 21st Amendment. (We’ll have another anniversary party then.)

• Most American beers are between about 4% and 6% alcohol (Budweiser is 5%), and can go higher, but several states still have laws regarding what is known as “3.2 beer.” Some, including Colorado and Oklahoma, allow 3.2 beer to be sold in supermarkets and convenience stores, while stronger beer must be sold in licensed liquor stores (and only at room temperature).

• Photograph from Amazing Facts, and they have several more from Prohibition America, and from April 1933.