Shrouded in forest, this small island appears to float peacefully on the Lower Lake in Killarney National Park. Behind the trees is what’s left of a 7th-century monastery that flourished for 1,000 years. It’s thought that Brian Boru, the great Irish chieftain, and St. Brendan the Navigator received their education here. From 950 to 1320, the “Annals of Innisfallen,” a chronicle of early Irish history, was written at the monastery. You can reach Innisfallen by rowboat, available for rental at Ross Castle ★.