Whether you're headed to Dublin, Belfast, Galway or Cork, as your plane flies over Ireland's low, rolling hills and patchwork of green fields it'll be clear to see why they call it the Emerald Isle. It's the mild but temperamental climate that causes that lushness; you can see four seasons in one day here, even if three of them are winter. Here in the land of saints and scholars, visitors can explore the ancient sacred sites of Newgrange and Clonmacnoise, gaze upon the Book of Kells at Trinity College, or simply soak up the atmosphere in pubs that inspired writers from Flann O'Brien to Brendan Behan to James Joyce. And then there's the glorious coastline: The Cliffs of Moher and the Giant's Causeway may be the big-hitters, but there's plenty more drama to unfold in the 2,500-kilometer Wild Atlantic Way tourism trail in the Republic and the Causeway Coastal Route in Northern Ireland.