© Licensed to London News Pictures. 26/04/2016. Warsaw, Poland. Nuns taking part in a procession through Warsaw's Old Town in commemoration Corpus Christi (Boze Cialo). Corpus Christi (Body of Christ) is a Catholic feast celebrated as a national public holiday in Poland. It is the day when the Catholic Church commemorates the practice of Holy Eucharist, or Communion. Photo credit: Rob Arnold/LNP