The First Lady along with Malia, 14, and Sasha, 11, viewed the Book of Kells, a ninth-century gospel manuscript inside the university grounds in Dublin city center on Monday afternoon.
They also pored over archives documenting the Obamas’ Irish ancestry. The President's great-great-great grandfather was a shoemaker in Moneygall, Co. Offaly.
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Thrilled, girls? First Lady Michelle Obama and
her daughters, Sasha (center) and Malia (right) tour the Old Library
Building at Trinity College in Dublin on Monday
Digging into the past: The First Family look
through archives documenting the Obama's Irish Ancestry during their
visit on Monday
Happy holidays! Sasha and Malia Obama look a
little bored as they are shown the historic books at Trinity College by
Dr Patrick Prendergast
The President, his wife and daughters touched down in Belfast amid the biggest security operation ever mounted in Northern Ireland.
Air Force One arrived at Aldergrove International Airport, 20 miles north of the city, where the President emerged from the plane with his family.
While Obama holds talks with other world leaders at the G8 summit in Northern Ireland, Michelle and their girls headed to the Republic.
The two-day trip is expected to cost the U.S. taxpayer more than $5.2million based on estimates after the First Couple's 2011 one-day trip cost $2.6million.
Don't get too excited girls! The Obama daughters
study the 'College Harp' - Ireland's oldest harp dating back from the
15th century and on which Ireland's national emblem is based on
Come on, Mom! Michelle looks excited as the family delve into the Obama's Irish heritage... unlike her daughters
Family trip: US President Barack Obama waves as
he exits Air Force One with his daughter Sasha upon arrival at Belfast
International Airport, Northern Ireland, this morning to attend the G8
summit in Enniskillen
Touch down: US President Barack Obama touched in
Belfast today amid the biggest security operation ever mounted in
Northern Ireland
Holding hands: Barack Obama disembarks from Air Force One with his daughter Sasha, 11
High profile: Roads into and out of Belfast were closed to facilitate the president's visit
The family is also expected to meet the staff and families of the U.S. Embassy during their Dublin visit
They are reported to be staying in the Shelbourne Hotel and according to the Irish Independent Michelle and Obama and her party have booked out 30 rooms in the five-star hotel.
It is understood Michelle will stay in the luxurious €2,500-a-night Princess Grace suite.
Greetings: The President was met by Lord
Leiutenant Joan Christie, Minister of State for Northern Ireland Mike
Penning, Arlene Foster MLA and Michelle O'Neill MLA
Wet welcome: Malia laughs as Sasha looks down at her feet after arriving in the drizzly weather
Long trip: Obama put his arm around daughter Malia, while First Lady Michelle Obama walked with their elder daughter Sasha
OBAMA'S IRISH ROOTS
Barack
Obama's great-great-great grandfather was a shoemaker in Moneygall and
his son, Falmouth Kearney, left for New York in 1850.
Mr Kearney arrived in New York with his brother-in-law William and wife, Margaret Cleary, and they were destined for Ohio.
He had 10 children and later settled in Indiana as a farmer.
Obama's mother, Ann Dunham, was a descendant of one of Mr Kearney's daughters, Mary Ann Kearney, and Jacob William Dunham.
In Moneygall, although generations have passed, blood ties with the president still remain.
U.S. and Irish genealogists have detected several other distant Irish cousins of Obama living in Ireland and England, including Dick Benn and Ton Donovan, whose families live just across the border in County Tipperary and have farmed the same land for 250 years.
Mr Kearney arrived in New York with his brother-in-law William and wife, Margaret Cleary, and they were destined for Ohio.
He had 10 children and later settled in Indiana as a farmer.
Obama's mother, Ann Dunham, was a descendant of one of Mr Kearney's daughters, Mary Ann Kearney, and Jacob William Dunham.
In Moneygall, although generations have passed, blood ties with the president still remain.
U.S. and Irish genealogists have detected several other distant Irish cousins of Obama living in Ireland and England, including Dick Benn and Ton Donovan, whose families live just across the border in County Tipperary and have farmed the same land for 250 years.
In the evening they are scheduled to rejoin the president and fly to Berlin.
Obama was flown to Belfast City Airport by helicopter and then travelled to the Waterfront Hall conference centre where he spoke to an invited audience of 2,000 mostly young people and urged political leaders to develop the peace process.
On arrival at the Waterfront, the family were greeted by Northern Ireland's First and Deputy First Ministers Peter Robinson and Martin McGuinness.
Roads into and out of Belfast were closed to facilitate the president's visit.
Hundreds of police 4x4s lined the streets, while the Police Service of Northern Ireland helicopter patrolled the skies over the city.
Thousands of extra police officers were deployed to the province ahead of the G8 summit.
The one day trip that the Obama's took to Ireland in 2011 was estimated to cost the White House $2.6million.
So this two-day trip is likely to cost double that amount taking into account his daughters now need a security detail and the family have split up into two locations.
Trips on Air Force One cost the government about $180,000 per flight hour.
According to a book published last year Obama and his family cost the taxpayer $1.4billion per year.
His recent appearances in Israel cost taxpayers an estimated $10.9 million.
Last time Obama visited Ireland he headed to the tiny village of Moneygall, Co. Offaly where his great-great-great grandfather on his Kansas-born mother's side, Falmouth Kearney, lived until leaving for the United States in 1850 at the height of Ireland's Great Famine.
Tight schedule: The family were flown to Belfast
City Airport by helicopter and then travelled to the Waterfront Hall
conference centre
Supportive: Obama hugs his wife before delivering a keynote address
Tests: Obama declared peace in Northern Ireland a
'blueprint' for those living amid conflict around the world, while
acknowledging that the calm between Catholics and Protestants will face
further tests
Speech: Michelle Obama delivers a keynote address at Waterfront Hall in Belfast, ahead of the G8 Summit
Moving on: While Barack Obama holds talks with
other world leaders at the G8 summit in Northern Ireland, Mrs Obama and
their children are due to visit the Republic
Later today he will travel to the luxury Lough Erne golf resort in Enniskillen, Co Fermanagh, where the leaders of the world's eight wealthiest countries will converge for the two-day G8 economic conference.
While Obama is widely admired in Ireland, he doesn't have anything close to the fan base built by Bill Clinton, who made Northern Ireland peacemaking a top priority and visited both parts of Ireland three times from 1995 to 2000.
George Bush also visited Northern Ireland in 2008.
Slainte: President Barack Obama and First Lady Michelle Obama sip Guinness at a pub in Moneygall, Co. Offaly in 2011