IAEA Ball.

Vienna is known as the city of grand  balls, with more than 450 balls taking place annually,  providing more than 2000 hours of dancing. The Carnival season in Vienna is filled with more than 150 large formal balls and hundreds of smaller dances that are held from before New Year till Lent. The 2013/14 ball season opened with the Vienna Red Cross Ball held at the City Hall in November.  On New Year’s Eve, Le Grand Bal at the Hofburg Palace brought in the New Year.