Mr Biden was given a tour of Carlingford Castle alongside the Tánaiste (Irish Deputy Prime Minister) Micheal Martin.
Asked about his feelings on the visit, the president replied: “It’s wonderful. It feels like I’m coming home.”
Commenting on the wet weather, he added: “It’s fine, it’s Ireland.”
The US president is also visiting the border town of Dundalk, where he greeted crowds along Clanbrassil Street. About 5,000 people are in attendance.
Mr Biden also made a visit to a local cafe where he met with staff.
In the coming days, he is expected to speak to politicians at the Oireachtas (Irish parliament) and meet more relatives in Ballina.
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