Derry or Londonderry , is the second city of Northern Ireland and the fourth largest city on the island of Ireland after Dublin, Belfast and Cork. It is situated on the river Foyle in County Derry/Londonderry, close to county Donegal. It has a population of 100,000. Note that the name of the city is a point of political dispute, with unionists advocating the longer name, and nationalists advocating the shorter. A common attempt at compromise is to refer to the county as "Londonderry" and the city as "Derry", but this is not universally accepted.