What started as a religious feast to celebrate the saint who brought Christianity to Ireland has now become synonymous with partying, good food, and joyful Guinness-drinking.
From streets decorated with green shamrocks and leprechauns to cheerful nights in the pub, there is plenty to do in the capital to mark the big day.
But what exactly is the significance of this special occasion?
Here is everything we know about St Patrick’s Day, including its history and the traditional ways to celebrate it.
St Patrick’s Day was honoured at Cheltenham Festival in 2025
PA
When is St Patrick’s Day 2026?
St Patrick’s Day is always held on March 17, which falls on a Tuesday this year.
It’s not a bank holiday in the UK or a federal holiday in the US, but it is a public holiday in both Northern Ireland and the Republic of Ireland.
St Patrick’s Day, also known as the Feast of Saint Patrick, marks the date of the Irish patron saint’s death.
It is observed by religious branches including the Catholic Church, the Anglican Communion, the Eastern Orthodox Church, and the Lutheran Church. It was made an official Christian feast day early in the 17th century, before becoming an official Irish public holiday in 1903.
St Patrick was a fifth-century Romano-British Christian missionary and priest.
It’s believed he was born in Roman Britain, at Kilpatrick, near Dumbarton, Scotland, in 387. He was then kidnapped by Irish raiders and taken as a slave to Gaelic Ireland at the age of 16.
Celebrations underway Down Under at The Quiet Man Irish Pub in the Melbourne
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St Patrick claimed that during his time in Ireland, he found God, who told him a ship would be waiting at the coast to take him home.
Patrick studied to become a priest after going home, before returning to Ireland to convert the pagan Irish to Christianity.
What are St Patrick’s Day traditions?
Consumption of both food and drink has always been a big part of the day. Lent restrictions on eating and drinking alcohol were historically lifted so that revellers could wholeheartedly enjoy the celebrations.
Nowadays, the festivities often include traditional Irish foods, such as soda bread, as well as quintessential Irish tipples such as whiskey and Guinness.
“Drowning the shamrock” is an age-old St Patrick’s Day custom. This entails placing a shamrock at the bottom of the cup, before filling it and finishing the drink as a toast to either the people present, to Ireland, or to St Patrick himself.
It is said that St Patrick used shamrocks as a metaphor for the Christian Holy Trinity. As such, not only are they now a classic symbol of St Patrick’s Day, but also of Irish heritage more generally.
Green apparel, which is associated with Irish history and nationalism, and wearable shamrocks are synonymous with St Patrick’s Day. Common celebrations take the form of public parades and festivals, as well as cèilidhean, Irish traditional music sessions.
Since 2010, famous landmarks worldwide have also been lit up green in honour of the day. Sydney Opera House and the Auckland Sky Tower were the first to take part, and the trend has now spread to more than 300 landmarks in 50 countries.