Oktoberfest (German pronunciation: [ɔkˈtoːbɐˌfɛst] ; Bavarian: Wiesn, Oktobafest) is the world's largest Volksfest, featuring a beer festival and a travelling carnival, and is held annually in Munich, Bavaria, from mid- or late-September to the first Sunday in October. The annual event attracts more than seven million international and national visitors at its peak. Locally, it is called d'Wiesn, after the colloquial name for the fairgrounds, Theresienwiese. Oktoberfest is an important part of local culture, having been held since the year 1810 (with intermissions). Other cities across the world also hold Oktoberfest celebrations that are modeled after the original Munich event.

During the event, large quantities of Oktoberfest Beer are consumed: in 2014, 7.7 million L (2.0 million US gal) were served. Visitors also enjoy numerous attractions, such as amusement rides, side stalls, and games. There is also a wide variety of traditional foods available.

Oktoberfest originally took place in the 16-day period leading up to the first Sunday in October. In 1994, this longstanding schedule was modified in response to German reunification. As a result, if the first Sunday in October falls on the 1st or the 2nd, then the festival runs until 3 October (German Unity Day which is a public holiday). Thus, the festival now runs for 17 days when the first Sunday is 2 October and 18 days when it is 1 October. In 2010, the festival lasted until the first Monday in October (4 October), to mark the event's bicentennial.