Portsmouth, UK

 The United Kingdom’s only island city, Portsmouth has been an integral base for the British Royal Navy since 1194. The seaport’s proud naval heritage is on display everywhere you look — from the 557-foot-high, sail-shaped Spinnaker Tower to the Portmouth Historic Dockyard, where you can step aboard several British warships including Vice-Admiral Horatio Nelson’s flagship during the 1805 Battle of Trafalgar. (You can follow the naval commander’s footsteps through Old Town along the self-guided Nelson Trail.) Visit the D-Day Story to learn how Allied forces in World War II boarded landing craft in Portsmouth bound for Normandy; and explore the 16th-century Southsea Castle, supposedly designed by Henry the VIII himself. The Southsea resort area invites with a two-mile stretch of beach, an amusement pier, and plenty of coffee shops and cafés.