In New York a memorial dedicated to the 1m people who died in the Famine was unveiled by President McAleese and the city's Mayor, Michael Bloomberg. The monument recreates a Mayo farm in the heart of New York.
The structure, which cost $5m, displays a ruined stone cottage as the centrepiece of what is essentially a slice of historic rural Ireland transplanted to lower Manhattan.
"We will not forget the tragedy that brought so many Irish emigrants to these shores," the President said, "nor the generosity of America in embracing our poor, restoring their dignity, and giving our ancestors the opportunity to forge this great nation."
The memorial is located in southern Manhattan's Battery Park City and has a view of the Statue of Liberty and Ellis Island -- the two landmarks that greeted generations of Irish immigrants to the United States.
The structure was designed by New York sculptor Brian Tolle.