Oktoberfest is a world-famous beer festival and traveling carnival held annually in Munich, Bavaria, Germany. It is the world's largest Volksfest (folk festival), running from mid- or late-September to around the first Sunday in October, with more than six million international and national visitors attending the event.

Oktoberfest originated on October 12, 1810, in celebration of the marriage of Crown Prince Ludwig of Bavaria (who later became King Ludwig I) to Princess Therese of Saxe-Hildburghausen. The festival concluded five days later with a horse race held in an open area that came to be called Theresienwiese. The following year the race was combined with a state agricultural fair, and in 1818 booths serving food and drink were introduced.

Today, Oktoberfest has evolved into a massive and internationally recognized event. Oktoberfest is a two-week celebration of Bavarian culture, featuring beer, food, music, and dancing. There are 14 large beer tents, each run by a different Bavarian brewery, as well as numerous smaller tents and booths serving food and drinks. 

Key features of Oktoberfest include:

Beer Tents: The festival is famous for its large beer tents, each run by different Munich breweries. These tents serve a variety of traditional German beers, with the most popular being Märzenbier, a strong, amber lager. Märzenbier is the traditional beer served at Oktoberfest. It is a strong lager that is brewed specifically for the festival.

Traditional Food: Alongside beer, Oktoberfest offers a wide range of traditional Bavarian foods such as sausages, pretzels, roast chicken, pork knuckles, and sauerkraut. Bratwurst, pretzels, and sauerkraut are some of the most popular food items at Oktoberfest. Other popular dishes include roasted chicken, pork knuckles, and dumplings.

Live Music: The beer tents feature live music, including traditional German bands and modern music acts. It's common for attendees to dance on the benches and tables to the music.

Carnival Rides and Games: In addition to food and beer, Oktoberfest grounds include an amusement park with various rides and games, making it a family-friendly event.

Traditional Clothing: Many visitors and even some of the locals dress in traditional Bavarian attire, such as lederhosen (leather shorts) for men and dirndls (traditional dresses) for women.

Parades: There are often parades, including the grand opening procession and traditional costume parades.

Cultural Events: Oktoberfest showcases Bavarian culture with events like dance performances, craft exhibitions, and more.

Massive Crowds: Millions of people from around the world attend Oktoberfest each year, making it a truly international celebration.

It's important to note that while the Oktoberfest in Munich is the most famous and largest, similar Oktoberfest celebrations are held in many cities worldwide, often with a focus on German beer, food, and cultural traditions.