Mayor James Walker and Roderick Kennedy, the event's commissioner, roll up Fifth Avenue in New York's 170th St. Patrick's Day parade. The city's first was held in 1762, more than a decade before the signing of the Declaration of Independence.
A little boy steals a kiss while his mother looks on. America's first St. Patrick's Day parade was actually held in Boston in 1737.
This child gets a bird's eye view of the parade. St. Patrick's Day became an official public holiday in Ireland in 1903. Dublin held the country's first parade in 1931.
The parade follows a 1.5-mile route along Fifth Avenue, lasts about five hours, and is always led by the 69th Infantry Regiment (New York).
A baton twirler leads the Xavier University band up Fifth Avenue. In Ireland, St. Patrick's Day was traditionally a Catholic feast day and a holy day of obligation. People had the day off from work, went to Mass and had a family meal together.
Actress Maureen O'Hara photographs the parade from the corner of 64th Street and Fifth. It is always held on March 17, the day Saint Patrick is thought to have died.
Jackie Kennedy stands on her tiptoes to get a better view. Today, more than 100 St. Patrick's Day parades are held in the United States. New York and Boston hold the largest celebrations.
Senator Robert F. Kennedy is flanked by police as he tries to make his way through a crowd of supporters to the St. Patrick's Day parade. His presidential campaign started the day before.
Mayor Ed Koch, who referred to himself as "Ed O'Koch," always marched in the parade in his signature Irish sweater.
Kilts and bagpipes are Scottish, but Saint Patrick was thought to have lived in Scotland, so their inclusion in the parade does make some sense.
Cardinal O'Connor watches kilted pipers passing by from his chair in front of St. Patrick's church.
Senate candidate Hillary Clinton holds a baby handed to her from the crowd. She was running against New York Mayor Rudy Giuliani for the senate seat.
Giuliani received loud applause at 2002's parade, as one of the largest crowds ever came out to remember those lost in the September 11 attacks.
That same year, former Mayor Michael Bloomberg marched and called for a moment of silence to honor those killed on 9/11.
The shamrock has been the symbol of Ireland since the 18th century. Trifolium dubium, the wild-growing three-leaf clover that some botanists consider the official shamrock, is an annual plant that germinates in the spring.
Brightly costumed Irish step-dancers float up Fifth Avenue.
Fire Chief Michael Bradley of the 4th Battalion has shamrocks on the mind as he marches up Fifth Avenue. Saint Patrick is said to have used the shamrock to explain the Holy Trinity.
A marching group moves past a giant Abercrombie & Fitch billboard.
Police officer Donald Swartz proposes to his girlfriend, Stephanie Hester, during the 245th parade. St Patrick's Day is considered the luckiest day of the year to get married.
This Jack Russell is all Irish for St. Patrick's Day. The parade is held on March 17, unless that 17th falls on a Sunday. When that happens, the parade is held on Saturday, the 16th.
Cardinal Edward Egan poses for a photo during the 248th parade. There are more Americans of Irish descent than there are Irish people in Ireland. (Some 36.3 million Americans reported they had Irish ancestry in 2008. At the time, the population of Ireland was 4.4 million.)
Two girls from Irish-American Society wait to perform.
Last year, 200,000 marchers participated in the parade, including police, military, firefighters, bands, county associations and emigrant societies. Over a million spectators lined the streets.
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