U.S. President Barack Obama opens a four-country, six-day European tour Monday in Ireland, where his largely ceremonial visit will highlight America's deep ties with the Irish. Air Force One is due to land in Dublin on Monday morning. The centerpiece of Obama's 24-hour stop on the Emerald Isle will be a visit to Moneygall, the tiny village where Obama's maternal great-great-great-grandfather was born. Obama will also meet with Irish leaders and deliver a speech in the center of Dublin that is expected to celebrate Irish culture. From Ireland, Obama will travel to England, France and Poland.