This is a vacation every member of the family will love: You'll visit eight amazing cities in four different countries—and even when you're at sea, you'll be entertained every minute. Itinerary highlights include the ancient monuments of Rome, Venice's canals, Dubrovnik's medieval ramparts, Barcelona's wild architecture, and the Renaissance treasures of Florence.

"Fun Ship," indeed: Liberty's pool deck has a 214-foot water slide at one end and an enormous movie screen at the other, and there are tons of fun, supervised opportunities for kids to play and mingle. The younger set can choose from arts and crafts, trivia, and talent shows; older kids get dance parties, late-night movies, and teens-only lounges and shore trips. Find out more.

Carnival is dedicated to family cruising, offering a huge variety of organized activities for kids age 2 through 17, as well as child care for infants on up. Many cabins offer extra beds for kids, or you can book a “family cabin” with bigger windows and bedding for four. There's plenty of adult fun too, with an excellent alternative restaurant, the Czar's Palace Casino, and Spa Carnival. Find out more about kids’ programs on Carnival Cruise Line.