There’s more than a millennium of history in this seaport on Ireland’s southeastern coast, the oldest city in the country. Founded by the Vikings in 914 C.E., Waterford celebrates its ancient lore and legends in the “Viking Triangle,” the original section of the city that now houses several museums, including the stone fortress known as Reginald’s Tower. Named for Viking founder Ragnall, it features a vertigo-inducing spiral staircase and showcases treasures from the era such as the 1,000-year-old Waterford Kite Brooch and a 9th-century sword. Also in the heart of the city is Christ Church Cathedral, constructed in 1773 in the Georgian Waterford architectural style. Now home to about 53,000 residents, Waterford is perhaps best known for its crystal, which has been produced here since the late 18th century. For fans of its distinctly cut and engraved tableware and decorative glassware, a factory tour is a must—or check out the oldest surviving Waterford piece, a decanter from 1789 that's on display in the Bishop's Palace. The rolling countryside just outside the city offers a chance to visit the castles, gardens and quaint villages for which Ireland is famed. Just remember: It all began right here amid the old stone streets of Waterford, which takes its name from the Viking moniker Vadrarfjordr.