Visby

Visby, on the Swedish island of Gotland, keeps one of the most complete town walls in northern Europe. Built up in stages through the Middle Ages and raised to its full height around 1300, it runs for roughly 3.4 km around the old Hanseatic port, with 27 ground towers and nine smaller saddle towers still standing. Inside, the ruins of medieval churches sit roofless among lanes of old houses and cottages, so the town reads as a real place that grew old rather than a set. You can walk the whole circuit outside the wall in an afternoon. High summer brings the ferry crowds; late spring and early fall are quieter and still light late into the evening.