On the banks of the Elbe, just before its confluence with the River Rhin, passengers will spy a colorful array of historic houses and a harbor fronted by an assembly of fishing boats and sailing ships. This is the Glückstadt, or “Lucky City,” which was founded in the early 17th century by King Christian IV of Denmark and which quickly became an important trading center. Today it offers a charming reconstructed town square with an atmospheric daily market.