University College Dublin (also known as UCD), formally known as University College Dublin – National University of Ireland, Dublin is Ireland's largest university, with over 1,300 faculty and 30,000 students. It is located in Dublin, the Irish capital.

The university originates in a body founded in 1854 as the Catholic University of Ireland with John Henry Newman as the first rector, re-formed in 1880 and chartered in its own right in 1908. The Universities Act, 1997 renamed the constituent university as the "National University of Ireland, Dublin", and a ministerial order of 1998 renamed the institution as "University College Dublin - National University of Ireland, Dublin".

Originally located in the centre of the metropolis, most of the university's faculties have since been relocated to a 148 hectares (370 acres) park campus at Belfield, four kilometres to the south of the city.