Limerick, Ireland

Limerick sits on the River Shannon as Ireland's third-largest city, home to roughly 102,000 residents in a settlement founded by the Vikings in 922. King John's Castle, built in 1212 on King's Island, still stands with its 13th-century walls and 18th-century barracks, while the 1168 Saint Mary's Cathedral ranks as the oldest active building in the city. The 1691 Treaty Stone marks the Siege of Limerick that ended the Williamite War, and the city's 1799 lace industry later produced the trim on Queen Victoria's wedding dress. Frank McCourt set his 1996 memoir Angela's Ashes in its 1940s lanes, leaving a story many readers still trace through the modern streets.