The Ducasse d'Ath is a traditional parade held to mark the victory of David over Goliath. It takes place in the town of Ath in Belgium. It has been recognized as one of the Masterpieces of the Oral and Intangible Heritage of Humanity by UNESCO, under "Processional giants and dragons in Belgium and France".

The parade is held on the 4th Sunday of August every year and is characterized by the presence of large giants depicting many characters from local history.

The city of Ath was founded in 1140 by Baldwin IV, Count of Hainaut by buying territory from his liegeman, Gilles de Trazegnies. The city experienced considerable expansion in the 14th century, with a church dedicated to St. Julian of Brioude coming up outside the enclosure of the walled city. 

The procession used to begin at the church and proceed to the new town. The 4th Sunday of August was chosen so that it fell near the feast day of St. Julien which is on August 28. The large biblical figures in the procession also served the purpose of catechizing a largely illiterate population.

The 700-year-old Giants of Ath festival has long slipped free of its religious origins, but Goliath remains the star. The giants’ parade depicts the marriage of the biblical figure and his fight with David, played by a local boy.

The big day is the last Sunday in August, when seven giants, musicians and a giant horse (carried by 16 people) parade through the town. For more folklore, the Maison des Géants museum, in an 18th-century townhouse, is a colourful guide to this tradition. 

According to theguardian.com