2 Best Sights in Dublin Environs, Ireland

The stately 18th-century Slane Castle overlooks a natural amphitheater, a bowl-shape hollow formed by surrounding hills. In 1981 the castle's owner, Anglo-Irish Lord Henry Mount Charles, staged the first of what have been some of Ireland's largest outdoor rock concerts; up to 100,000 fans have gathered to watch stars including U2, Bob Dylan, and the Rolling Stones. A tour of the Gothic-style castle includes the main hall, with its delicate plasterwork and beautiful stained glass, and the dazzling neo-Gothic ballroom completed in 1821 for the visit of King George IV. The stunning parklands were laid out by Capability Brown, a famous 18th-century landscape gardener. Slane Castle produces its own whiskey and has fun tasting tours, including a how-to-make-an-Irish-coffee tour.

The long-abandoned but still largely intact castle was once the largest Anglo-Norman fortress in Ireland. Trim Castle dominates present-day Trim from its 2½-acre site, which slopes down to the river's placid waters. Built by Hugh de Lacy in 1173, the castle was soon destroyed, then rebuilt from 1190 to 1220. The ruins include an enormous keep with 70-foot-high turrets flanked by rectangular towers. The outer castle wall is almost 500 yards long, and five D-shape towers survive. So impressive is the castle that it was used as a medieval backdrop in the movie Braveheart. You are free to roam the castle, but the admission price includes a house tour.