The Upper Middle Rhine Valley is a 65-kilometer stretch of the Rhine River between Koblenz and Bingen that reads like a fairy tale brought to life. Recognized as a UNESCO World Heritage site, this dramatic gorge is studded with more than 40 castles and fortresses perched on steep, vine-covered hillsides. The river carves through the Rhenish Slate Mountains, creating towering cliffs, hidden coves, and picturesque wine villages that have inspired painters, poets, and composers for centuries. At the narrowest point, the legendary Lorelei rock rises 120 meters above the water, where according to legend a beautiful maiden once lured sailors to their doom with her enchanting song.

The best way to experience the valley is aboard one of the KD Rhine cruise ships that ply the river between the major towns. From the deck, castle after castle unfolds against the landscape: the hilltop fortress of Marksburg, the only Rhine castle never destroyed; the island toll castle of Pfalzgrafenstein rising from mid-river; and the brooding ruin of Rheinfels above the town of St. Goar. Along the banks, terraced vineyards produce some of Germany’s finest Riesling wines, and nearly every village hosts a wine festival during the autumn harvest season.

Pro tip: Combine the cruise with the train for maximum flexibility. Ride the KD ferry downstream (the more scenic direction) from Bacharach to St. Goar, explore the Rheinfels Castle ruins, then catch the regional train back. Trains run frequently along both banks, and many castles are a short walk from their own stations.