It’s almost time to start picking shamrocks and watching out for the leprechauns. Yes, on March 17 the world will once again celebrate St Patrick’s Day. Every year on this day the people of Ireland and those of Irish ancestry, throw a massive party. And what a celebration it is! There are often more non-Irish revellers at these events and there is some truth in the claim that "for a day, the world turns Irish".

And that means that everyone dresses in green, eats Irish food and, most importantly, have their fill of a traditional Irish drink like Guinness or Bailey's Irish Cream. Certainly, when it comes to having fun, the Irish have always punched above their weight. From a small island off the coast of England, they have spread their influence across the globe, always retaining a great sense of national pride.

Witness to this is the number of Irish pubs dotted around the globe and regarded by one and all as bastions of good cheer. These days big international chain groups have been started to cater for the demand. It has been claimed that there are more Irish pubs in the world than there are Irishmen. Certainly, it is difficult to find any city or town that doesn't have some sort of Irish pub.

But let's get back to St Patrick. For a person one who is so celebrated, there is actually very little known about him. One of the folklores is that he drove all the snakes out of Ireland. The fact that no snakes are native to Ireland is just a niggly detail that everyone chooses to ignore. Closer to the truth is that he represents the conversion of the Pagans to Christianity. But no-one squabbles about the historical details: this day is all about being Irish.

Of course, the heart of the worldwide celebrations is in Dublin. For six days, from March 12-17, the city throws a party with music, plays, dancing and late-night drinking. It culminates in a festival parade on the final day, with thousands of participants weaving their way through the city streets accompanied by marching bands, theatre companies and artists.

This year's theme is "The Sky's The Limit". Organisers estimate that over 500,000 people will attend the events over the six days. For the best view, you can buy a grandstand seat. Ireland's other cities all hold their own parades and festivals, including Cork, Belfast, Derry, Galway, Kilkenny, Limerick, and Waterford. Parades also take place in other Irish towns and villages, however small.

Some of the most popular events take place in North America, where a large mass of people claiming Irish ancestry. In fact, the first St Patrick's Day gathering was held in Boston in 1761. This was followed in 1766 by the first festival parade, when Irish soldiers took to the streets of New York City to the sounds of marching bands. St Patrick's Day traditional march was born.

The Big Apple still throws the biggest party every year, with around 150,000 marchers and three million spectators. It seems every inch of the route is packed with people wearing orange and green and sporting shamrocks and leprechauns in one form or another. Make sure you book a hotel early over this period Boston, Chicago, Philadelphia, and Savannah also celebrate the day with parades including between 10,000 to 20,000 participants.

In fact, some American have developed interesting traditions around the event. Chicago dyes its river green over this period to honour its Irish residents, a tradition that started in 1961. The city of Savannah in Georgia dyes its fountains green, while Missouri university students paint 12 city blocks green with mops before their annual parade.

On this day everyone "feels the luck of the Irish", but the early settlers were not that welcome. When the great "potato famine" hit Ireland in 1845, nearly a million poor Irish Catholics headed for America to escape starvation. They were poorly educated and despised for their funny accents. When they first marched in the streets to celebrate St Patrick's Day, newspaper cartoons portrayed them as drunk, violent monkeys.

Only when they started to organise themselves politically and became an important voting bloc did the city fathers start to take them seriously. The "green machine" became a vital swing vote and ever since then they have been courted by politicians. In 1948, even President Harry Truman attended the New York parade, finally ending an era of prejudice. Then came the Kennedy's and the Irish Catholics became a major political force.

In Britain, the Queen Mother always presented bowls of shamrock flown over from Ireland to members of the Irish Guards stationed in London, most of whom come from Ireland and Northern Ireland. One of the popular London venues is Trafalgar Square - and last year the water in the fountains was dyed green for the first time. The Cheltenham Festival horse racing event on this day attracts a large Irish contingent.

Other international centres which have big festivals include Sydney in Australia, reputedly the largest in the southern hemisphere, and Montreal in Canada. A recent phenomenon has been for baseball teams to wear green versions of their kits over this period. In fact, there is a definite trend towards people of diverse cultures and nationalities across the globe dressing up in green on this traditional day. So, go on, have some fun this St Patrick’s Day.