Chicago estimated that last year somewhere around 75,000 people from all over the world came to the city to celebrate St. Patrick's Day, at the city's parades and bars — and to watch as the city dyed its river green as it has for more than 60 years now.
Further south in Georgia, the historic city of Savannah traces its St. Patrick's Day roots all the way back to 1824.
The holiday has largely become a secular celebration of revelry as merrymakers imbibe, feast and enjoy.
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Chicago's annual St. Patrick's Day parade is the largest outside of Dublin's in Ireland.
Drinking alcohol is a big part of the holiday. St. Paddy's Day is the third most popular drinking day of the year. The average person drinks 4.2 alcoholic beverages on that day.
The holiday started as a way to quell homesickness as Irish immigrants settled in the United States. It honors the patron saint who brought Christianity to Ireland. It was the emigrants to the U.S. who largely turned the holiday into a celebration of all things Irish.
Boston held the first St. Patrick's Day parade in the U.S. back in 1737, followed by New York City's in 1762.
While some of the traditions of St. Patrick's Day in the United States were adopted by the Irish themselves over the years, the country did it largely for the sake of tourists.
