NEW YORK (AP) — St. Patrick’s Day, the annual celebration of all things Irish, is being marked in cities across the country on Monday with boisterous parades and celebrations.

New York City hosts one of the largest and oldest parades in the United States.

The rolling celebration, now in its 264th year, is taking place along Manhattan's famed Fifth Avenue. Some 150,000 take part in the march, according to organizers.

Major celebrations are also planned on Monday in Savannah, Georgia, and other American communities, though some of the cities most transformed by Irish immigration held festivities over the weekend.

Chicago 's St. Patrick's Day celebration, which is punctuated by turning its namesake river bright green with dye, happened Saturday. Boston and Philadelphia marked the occasion Sunday.

Across the pond, the Irish capital of Dublin culminates its three-day festival with a parade Monday. Cities such as Liverpool, England, another city transformed by Irish immigration, also host celebrations on the St. Patrick's feast day.

The parades are meant to commemorate Ireland's patron saint but have become a celebration of Irish heritage globally.

Festivities on March 17 were popularized by Irish immigrant communities, who in the 19th century faced discrimination and opposition in the U.S.

The New York parade dates to 1762 — 14 years before the U.S. Declaration of Independence.

It stepped off at 11 a.m. as marchers headed north along Fifth Avenue from East 44th Street to East 79th Street in Manhattan.

A bevy of local politicians, from the mayor to the governor, are expected to walk the route along with school marching bands and traditional Irish pipe and drum ensembles and delegations from the New York Police Department and other organizations.

The grand marshal of this year’s parade in New York City is Michael Benn, the longtime chairman of the Queens County St. Patrick’s Parade held in Rockaway Beach.

A man on a float encourages the crowd to cheer louder during the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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The Chicago River is dyed green as part of annual St. Patrick's Day festivities Saturday, March 15, 2025, in Chicago. (AP Photo/Erin Hooley)

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April Loh, left, and Marie Maia, take a selfie while enjoying a Kiwi Mule mocktail, made without tequila, during the sober Saint Patrick's Day celebration at the Whistler House Museum, Thursday, March 13, 2025, in Lowell, Mass. (AP Photo/Charles Krupa)

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A Shriner motors by the crowd during the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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The Chicago River is dyed green as part of annual St. Patrick's Day festivities Saturday, March 15, 2025, in Chicago. (AP Photo/Erin Hooley)

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Performers shoot muskets at the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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A drummer performs during the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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The Chicago River is dyed green as part of annual St. Patrick's Day festivities Saturday, March 15, 2025, in Chicago. (AP Photo/Erin Hooley)

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A sheet metal worker high-fives the crowd during the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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Michele Hunter, of Pawlet, Vt., center left, and Erin Riley, of Saugus, Mass., cheer a performer at the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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Spectators watch the St. Patrick's Day parade from a balcony, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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Tommy McCarthy and his wife Louise Costello, owners of the Burren Pub, play an Irish tune, Wednesday, March 12, 2025, in Somerville, Mass. (AP Photo/Robert F. Bukaty)

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A man dressed as a leprechaun slaps hands with the crowd during the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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Empty containers used for homemade drinks overflow the garbage cans after the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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Spectators cheer at the St. Patrick's Day parade, Sunday, March 16, 2025, in Boston, Mass. (AP Photo/Robert F. Bukaty)

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The Chicago River is dyed green as part of annual St. Patrick's Day festivities Saturday, March 15, 2025, in Chicago. (AP Photo/Erin Hooley)

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