The Oktoberfest tradition started in 1810 to celebrate the marriage of the Bavarian Crown Prince Ludwig. It has since grown into a huge annual festival held over 16-18 days in Munich, Germany, attracting over 6 million people each year. Key events include the opening ceremony where the mayor taps the first keg of Oktoberfest beer, parades, concerts, and drinking beer and eating traditional foods in the many large festival tents. The six breweries permitted to serve beer sell Märzen-style beer to crowds enjoying polka music and dancing.