US President Barack Obama's speech in Dublin on Monday night will be entirely open to the public with no tickets required.
Mr Obama will deliver the keynote address at an entertainment event in College Green at around teatime.
The tens of thousands of people expected to attend the speech will have to turn up hours beforehand due to security considerations.
The speech will be the largest event during the president's whistlestop 24-hour visit next week.
First Lady Michelle Obama and Taoiseach Enda Kenny will also take part, and musical acts will warm up the crowd. Details are still not confirmed, but organisers say it will involve "many well-known Irish artists".
The Government confirmed last night that President Obama will call on President Mary McAleese at Aras an Uachtarain and meet with Mr Kenny. During Monday's visit the president will also take a trip to his ancestral home in Moneygall, Co Offaly.
In a statement, the Government said the College Green event will be open to members of the public, is free of charge and tickets will not be required.
"To facilitate the large number of people expected to attend, security gates will open at 2pm on the day," the statement said.
Members of the public are being advised to enter the security gates at the intersection of Parliament Street and Dame Street in front of Dublin Castle.
Those attending can then proceed from the north on Parliament Street or from the west on Dame Street.
"Members of the public are asked to please allow plenty of time to get to the event as many streets will be closed to traffic and parking in the city will be greatly limited."
Signs and banners along with food and drinks won't be allowed inside the event site -- but cameras and mobile phones will. Further details will be announced over the weekend.
Mr Obama is set to follow in the footsteps of his predecessor Bill Clinton who addressed tens of thousands at College Green in 1995.
The area will be closed off on Sunday and Monday.
Mr Obama's officials were initially thought to be reluctant to go for College Green as it would be seen as the same as President Clinton's event.
Gardai vetoed the White House's idea of Mr Obama making his speech in front of Daniel O'Connell's statue on O'Connell Street because it would mean shutting down the quays for two days.