At precisely noon on September 19, following a parade through the city, the mayor of Munich, Germany, will tap the first keg of Oktoberfest with a cry of “O'zapft is (It’s tapped)!” From that moment until a traditional gun salute brings the 16-day festival to a close, more than 6 million visitors are expected to consume enough beer to fill three Olympic-size swimming pools. In between gulps, there will also be traditional Bavarian food and amusement park rides on offer, including what organizers are billing as the world’s largest haunted house.

Many revelers at this year’s festivities may not even know that they’re in essence commemorating a wedding. Back in October 1810, Bavaria’s crown prince (the future King Ludwig I) married Princess Therese of Sachsen-Hildburghausen. Bavaria, in present-day southern Germany, had become a kingdom just four years earlier. So to build up national unity, the royal family invited all of Munich, the capital of Bavaria, to celebrate on the fields just outside the city gates. Over the course of six days, these fields, now known as Theresienwiese (Therese’s meadow), or Wies’n for short, hosted a fair, a parade and, most notably, a horse race attended by some 10,000 spectators.

This inaugural Oktoberfest proved so successful that it was repeated the following year, with an agricultural show and another horse race as the marquee events. By 1818, a carousel, swings, tree-climbing competitions, wheelbarrow races and goose chases were also in place, along with beer and food stands. Over time, Oktoberfest was prolonged, and its start date was pushed forward to September for better weather. Meanwhile, the development of a regional railroad network allowed visitors from outside Munich to join in. Mechanical amusement park rides made their first appearance in the 1870s, followed by enormous beer halls in the 1890s and a roller coaster in 1908. Additional entertainment included magic shows, carnival booths, music and menageries.

Twenty-four Oktoberfests have been cancelled over the years due to wars, hyperinflation and cholera epidemics. Upon taking power in 1933, the Nazis banned Jewish vendors from participating and decorated the Wies’n with Swastikas. In 1980, an alleged neo-Nazi set off a bomb that killed 13 and injured more than 200. Yet Oktoberfest has always managed to bounce back from these crises. Since the 1980s, it has grown increasingly popular—and expensive, according to Simone Egger, an ethnologist from Munich. In the last 15 years, she said, it has even become customary for locals and tourists alike to wear traditional Bavarian clothing, such as lederhosen and dirndl dresses.

Egger explained that the beer, which is mostly lager, comes in 1-liter glasses that cost over 10 Euros ($11.34) apiece. The food, on the other hand, varies from roast chicken and grilled sausages to pork with dumplings and big pretzels. For the first time, beer-flavored ice cream will also reportedly be on the menu. “The whole thing is like a big rush,” Egger said. “You eat and drink, it is like you are out of daily life for a day or a weekend. You don’t care about low carb and calories, you just feel free.” (Many visitors apparently feel too free: in addition to run-of-the-mill wallets, phones and keys, a prosthetic leg, dentures, wedding rings and a Superman costume have all turned up at Oktoberfest’s famous lost and found.)

Though Munich hosts the original and largest Oktoberfest, it is far from the only game in town. In the United States alone, there are at least 110 Oktoberfest celebrations, the largest of which, Oktoberfest Zinzinnati, attracts roughly a half-million visitors annually. “It’s kind of our nod to Munich and what a great event that is [but with] a unique American spin,” said Patrick Sheeran, vice president at the Cincinnati USA Regional Chamber, which produces the festival. Taking place from tonight to Sunday, it will feature over 80 varieties of beer, not to mention one thing Munich surely lacks: former Cincinnati Bengals quarterback Ken Anderson leading a giant chicken dance.