Thursday is St Patrick's Day, which commemorates the patron saint of Ireland, but nowhere is the feast day celebrated on a grander scale than in the US, where cities host parades, dye their rivers green and countless revellers don leprechaun outfits.
The US has deep Irish roots, with millions of people arriving from Ireland in the 19th century to start new lives as the potato famine devastated their homeland.
Marking the day's significance on the US calendar, Ireland's Prime Minister Micheal Martin is in Washington.
He was supposed to hold in-person talks with President Joe Biden, but his trip took an unexpected turn when he tested positive for coronavirus late on Wednesday. He had met the president briefly at a gala before testing positive.
Mr Martin left in the middle of the event and was conducting his St Patrick's Day appointments online on Thursday.
“I’m doing good and I think that reminds of the vaccines and that the vaccines prevent severe illness,” Mr Martin told Mr Biden in a video meeting.
Mr Biden will be speaking at an Annual Friends of Ireland Luncheon hosted by House Speaker Nancy Pelosi.
Later, he and first lady Jill Biden will be hosting a St Patrick's Day event at the White House.
New York City hosted a St Patrick's Day parade, held annually since 1762, and it is the largest and oldest parade in the world celebrating the holiday.
It signalled a return to tradition for the Big Apple. The parade on Thursday was the first since the pandemic led to the event's cancellation in 2020 and 2021.
The return also lined up with the city's reopening of sorts as mask and vaccination rules were lifted by Mayor Eric Adams due to a lower level of coronavirus cases.
“This St Patrick’s Day, we honour those Irish immigrants who relocated and helped build our city and the many Irish Americans who serve New York City to this day,” the mayor said on Wednesday night before the celebrations.
In the Midwest, the Chicago River that runs through the city's centre was dyed green. The custom started in 1962 and Chicago marks the 60th anniversary of the tradition this year.
Other cities such as Indianapolis, Tampa and San Antonio also dye their rivers or canals green and host parades.