The Republic of Ireland occupies most of the island of Ireland, off the coast of England and Wales. Its capital, Dublin, is the birthplace of writers like Oscar Wilde, and home of Guinness beer. The 9th-century Book of Kells and other illustrated manuscripts are on show in Dublin’s Trinity College Library. Dubbed the "Emerald Isle” for its lush landscape, the country is dotted with castles like medieval Cahir Castle. Ireland Travel Guide video.