A trachtenfest is a festival where traditional German costumes are worn, such as dirndl for women and lederhosen for men.

A dirndl is a feminine dress originating in German speaking areas of the Alps. It is traditionally worn by women and girls in Bavaria (which is Southeastern Germany, Austria, Switzerland, Liechtenstein and Alpine regions of Italy).  It consists of a close-fitting bodice with low neckline, a blouse, and a wide high-waisted skirt plus apron.  A dirndl is considered a folk costume such as Tracht.  It was developed as the clothing of Alpine peasants between the 16th – 18th centuries, but today it is considered the traditional dress for women and girls in German speaking areas of the Alps. There are particular designs associated with different regions. In the late 19th century, the dirndl was adapted by the upper and middle classes as a fashion statement. There are many varieties of dirndl adapted from the original folk designs.