Ireland is the third-largest island in Europe. It lies in the Atlantic Ocean and it is composed of the Republic of Ireland (officially named Ireland), a state which covers five sixths of the island (south, east, west and north-west), and Northern Ireland; part of the United Kingdom, which covers the northeastern sixth of the island.

The population of the island is approximately 5.8 million people; 4.1 million in the Republic of Ireland (1.6 million in Greater Dublin) and 1.7 million in Northern Ireland (0.8 million in Greater Belfast).