The Feast of the Immaculate Conception (Festa da Imaculada Conceição) is a religious holiday to celebrate the conception of the Virgin Mary, who Catholics believe was born without original sin and in Portugal it is also a public holiday. For Portuguese Catholics the day has special significance, as Nossa Senhora da Imaculada Conceição (Our Lady of the Immaculate Conception) is the patron saint of Portugal. She was first chosen to be the country’s patron saint by Queen Isabel (who later became Saint Isabel Queen of Portugal) in 1320, who made the Immaculate Conception a day of celebration, but it wasn’t until 1646 that King João IV officially proclaimed Our Lady of the Immaculate Conception the patron saint of Portugal. The main focus of the day for Catholics is to attend a Mass, but in many places there are also processions through the streets, where a statue of Mary is carried. She is also the patron saint of fishermen and in Quarteira, a coastal town in the Algarve, after being paraded through the streets of Quarteira, she is put on a boat and sailed around the Quarteira coast to bless the sea, accompanied by the boats of the local fishermen.
Banks, post offices and other public services are closed on this day (this includes some museums) and public transport runs to a reduced timetable. However, large shopping centres and shops in tourist areas should be open as usual. Churches will be closed to tourists while Mass is taking place.