The Feast of Corpus Christi (Body of Christ) or Boże Ciało is observed on the Thursday after Trinity Sunday in villages, towns and cities all over Poland. It is a national holiday, and virtually the whole town is involved in an organized procession that parades through the streets. A traditional procession leaves the church after mass and continues on the streets with banners and holy pictures. Young girls dressed in their first communion dresses scatter rose and other flower petals on the streets. These petals are for Christ, who is believed by Catholics to walk the streets with the people during the processions. In the central part of the procession is the shrine of The Holy Host. Many people kneel in the street as the shrine passes them. The procession walks around the streets stopping at various temporary shrines to sing hymns and pray. The shrines are decorated with branches from Birch trees, and members of the procession tear off twigs from these shrines for luck and happiness. Many homes display religious icons in their windows and traffic is stopped throughout the city.